Method for shading compensation of microphone array and audio acquisition device

Abstract

The application relates to a microphone array shielding compensation method and an audio acquisition device, the shielding compensation method comprising: classifying shielding conditions of a microphone array, and obtaining compensation values of each microphone of the microphone array under various shielding conditions through testing; identifying the shielding condition type and the shielding direction of the shielding object around the microphone array after the microphone array is installed; obtaining the corresponding compensation values of each microphone of the microphone array according to the shielding condition type and the shielding direction, and compensating the gain of the microphone according to the compensation values. In the application, the compensation values of each microphone under various shielding conditions are tested in advance, the gain of each microphone can be compensated according to the installation environment, the influence of the shielding object on the microphone array can be greatly reduced, the negative influence on the identification of the sound source direction can be avoided, and the receiving effect and accuracy of the microphone array are improved.

Description

Technical Field

[0001] This invention belongs to the field of microphone array technology, and relates to a microphone array occlusion compensation method and an audio acquisition device. Background Technology

[0002] A microphone array is an array of multiple microphones arranged in a specific geometric pattern. It captures, processes, and recognizes audio signals by processing the signals from the microphone array. Compared to a single microphone, microphone array technology offers higher accuracy and efficiency in noise reduction, voice enhancement, direction recognition, and distance measurement. It is widely used in speech recognition, speech translation, smart homes, conferencing systems, and wireless communication.

[0003] For aesthetic reasons, microphone array mounts are typically square, the same size as the ceiling panels, allowing for ceiling mounting. However, this creates obstructions around the microphone array. Under different obstruction conditions, the microphone array's gain changes, affecting its performance and accuracy, and negatively impacting sound source direction recognition. Therefore, microphone calibration is necessary to compensate for gain changes caused by obstruction. Current microphone array calibration methods usually employ a fixed approach: obstruction conditions are simulated before installation, and the compensation value for each microphone is determined through testing. This requires that the relative position of the microphone array to the obstruction during installation be exactly the same as in the simulation, with high precision, unaffected by installation angles or methods; otherwise, it will negatively impact the microphone's direction recognition. Therefore, the main problem we need to solve is how to install microphone arrays more conveniently without interfering with their direction recognition capabilities. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a microphone array occlusion compensation method and an audio acquisition device.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for compensating for occlusion in a microphone array includes the following steps:

[0007] S1. Classify the occlusion conditions of the microphone array in advance; and obtain the compensation value of each microphone in the microphone array under various occlusion conditions through testing;

[0008] S2. After the microphone array is installed, identify the type of obstruction around the microphone array and the location of the obstruction.

[0009] S3. Based on the type and location of the occlusion, determine the compensation value for each microphone in the microphone array, and compensate the microphone gain according to the compensation value.

[0010] Furthermore, in step S1, determining the compensation value for each microphone in the microphone array under various occlusion conditions through testing includes the following sub-steps:

[0011] S101. Number each microphone in the test microphone array according to its position;

[0012] S102. Test the microphone array under unobstructed conditions to obtain the signal strength of each numbered microphone under unobstructed conditions;

[0013] S103. Record the relative positional relationship between each numbered microphone and the obstruction under various obstruction conditions, and test the microphone array to obtain the signal strength of each numbered microphone under various obstruction conditions.

[0014] S104. Subtract the signal strength of the microphone numbered under the unobstructed condition from the signal strength of the microphone numbered under each type of occlusion condition to obtain the compensation value of the microphone numbered under each type of occlusion condition.

[0015] Furthermore, step S3 includes the following sub-steps:

[0016] S301. Based on the identified type of occlusion, the occlusion location, and the relative position of each microphone number to the occlusion object, determine the number of each microphone in the microphone array.

[0017] S302. Based on the identified occlusion type, determine the compensation value corresponding to each microphone number.

[0018] S303. Perform gain compensation on each microphone numbered according to the compensation value.

[0019] Furthermore, the microphone array includes a base and a plurality of microphones disposed on the base. The base is a regular polygon, and the plurality of microphones are arranged to form a rotationally symmetric figure, wherein the rotation angle of the rotationally symmetric figure is equal to the exterior angle of the regular polygon.

[0020] Furthermore, in step S103, one side of the seat is taken as the positioning side, and the relative positional relationship between the positioning side and the obstruction, as well as the relative positional relationship between each numbered microphone and the positioning side, are recorded.

[0021] In step S301, the positioning side of the microphone array base is first determined according to the occlusion situation and occlusion direction, and then the number of each microphone in the microphone array is determined according to the relative position relationship between each numbered microphone and the positioning side.

[0022] Furthermore, the base is square, and the rotation angle of the rotationally symmetrical figure formed by the arrangement of the multiple microphones is equal to 90°; the occlusion of the microphone array is classified into one-sided occlusion, adjacent two-sided occlusion, opposite two-sided occlusion, three-sided occlusion, and four-sided occlusion.

[0023] An audio acquisition device, comprising

[0024] A microphone array, wherein the microphone array is an array of multiple microphones arranged geometrically on a base;

[0025] The audio processing unit is used for sound source localization and speech enhancement processing of the signals acquired by the microphone array; and

[0026] The occlusion compensation unit is used to compensate the gain of each microphone in the microphone array using the occlusion compensation method of the microphone array.

[0027] Furthermore, the audio processing unit includes

[0028] The preprocessing module is used to preprocess the signals acquired by the microphone array;

[0029] The sound source localization module is used to identify the direction and distance of the sound source based on the signals collected by the microphone array;

[0030] The speech enhancement module is used to form a beam in a desired direction using beamforming technology, thereby extracting the sound source and suppressing noise; and to process the acquired speech signal to improve the quality and reliability of the speech; and

[0031] The output module is used to output the signal processed by the voice enhancement module to subsequent audio processing devices or embedded systems.

[0032] Furthermore, the occlusion compensation unit includes

[0033] The compensation value storage module is used to store the compensation value of each microphone in the microphone array under various occlusion conditions;

[0034] An occlusion recognition module is used to identify occlusion around the microphone array and the location of any obstructions; and

[0035] The adaptive algorithm module is used to determine the compensation value for each microphone in the microphone array based on the occlusion situation and occlusion direction, and to enable the audio processing unit to compensate the gain of each microphone in the microphone array according to the compensation value.

[0036] Furthermore, the occlusion recognition module uses an infrared sensor to collect the location information of occlusions around the microphone array, and identifies the occlusion situation around the microphone array and the location of the occlusions based on the location information.

[0037] In this invention, by pre-testing the compensation value of each microphone under various obstruction conditions, the gain of each microphone can be compensated according to the installation environment. This significantly reduces the impact of obstructions on the microphone array caused by different installation methods, avoiding negative impacts on the identification of sound source direction and improving the reception effect and accuracy of the microphone array. Furthermore, by not fixing the microphone numbers before installation and identifying the location of the obstruction and determining the microphone numbers after installation, any side of the microphone array can be aligned with the obstruction during installation, eliminating the need to align a fixed side of the microphone array with the obstruction during installation, thus making installation more flexible. Attached Figure Description

[0038] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0039] Figure 1 This is a flowchart of one embodiment of the microphone array occlusion compensation method of the present invention.

[0040] Figure 2 This is a schematic diagram of a microphone array structure.

[0041] Figure 3 This is a schematic diagram of the microphone assembly.

[0042] Figure 4 This is a flowchart for determining the compensation value of each microphone in a microphone array under various occlusion conditions through testing.

[0043] Figure 5 This is a schematic diagram showing the positional relationship between the four sides of the base, the four microphone components, and the obstruction when one side is blocked.

[0044] Figure 6 This is a schematic diagram showing the positional relationship between the four sides of the base, the four microphone components, and the obstruction when two adjacent sides are blocked.

[0045] Figure 7This is a schematic diagram showing the positional relationship between the four sides of the base, the four microphone components, and the obstruction when there is relative obstruction on two sides.

[0046] Figure 8 This is a schematic diagram showing the positional relationship between the four sides of the base, the four microphone components, and the obstruction when the base is blocked on three sides.

[0047] Figure 9 This is a flowchart of a sub-step of step S3.

[0048] Figure 10 This is a schematic diagram showing the distribution of each microphone component in the microphone array.

[0049] Figure 11 This is a structural block diagram of an embodiment of the audio acquisition device of the present invention.

[0050] The meanings of the labels in the attached diagram are as follows:

[0051] Microphones - 101, 102, 103, 104, 105, 106, 107, 108; Microphone assemblies - 110, 120, 130, 140; Base - 150; First side - 151; Second side - 152; Third side - 153; Fourth side - 154; Obstructions - 201, 202, 203. Detailed Implementation

[0052] The following specific examples illustrate the implementation of the present invention. The illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0053] Example 1

[0054] like Figure 1 As shown, a selected embodiment of the microphone array occlusion compensation method of the present invention includes the following steps:

[0055] S1. Classify the occlusion conditions of the microphone array in advance, and obtain the compensation value of each microphone in the microphone array under various occlusion conditions through testing.

[0056] The microphone array includes a base 150 and multiple microphones disposed on the base 150, the multiple microphones being arranged in a geometric array; the base 150 is a regular polygon, and the geometric shape formed by the arrangement of the multiple microphones is a rotationally symmetric figure, wherein the rotation angle of the rotationally symmetric figure is equal to the exterior angle of the regular polygon. Figure 2As shown, in this embodiment, the base body 150 is square. Since the exterior angle of a regular polygon is 90°, correspondingly, the rotation angle of the rotationally symmetric pattern formed by the arrangement of the plurality of microphones should be equal to 90°; therefore, in this embodiment, four microphone assemblies (110, 120, 130, 140) arranged at intervals of 90° in sequence are adopted. As shown Figure 3 , each microphone assembly includes eight microphones (101, 102, 103, 104, 105, 106, 107, 108) arranged in a line, so that 32 microphones are arranged to form an inclined "cross" shape. Of course, the geometric pattern formed by the arrangement of the plurality of microphones in the microphone array may also be a geometric pattern with a rotation angle of 90°, such as a "star" shape, a square, a circle, etc. When the microphone array is rotated 90° clockwise, the microphone assembly 110 rotates to the previous position of the microphone assembly 120, the microphone assembly 120 rotates to the previous position of the microphone assembly 130, the microphone assembly 130 rotates to the previous position of the microphone assembly 140, and the microphone assembly 140 rotates to the previous position of the microphone assembly 110, so that the geometric pattern formed after the 32 microphones are rotated by 90° remains consistent with that before rotation. Based on this feature, for the square microphone array adopted in this embodiment, the occlusion condition classification may include five types: one-side occlusion, two adjacent sides occlusion, two opposite sides occlusion, three-side occlusion, and four-side occlusion.

[0057] To facilitate numbering the microphone array, the four sides of the microphone array are sequentially defined as a first side 151, a second side 152, a third side 153, and a fourth side 154 in the clockwise direction. The microphone assembly aligned with the included angle between the first side 151 and the fourth side 154 is defined as the microphone assembly 110, and the other three microphone assemblies are sequentially defined as the microphone assembly 120, the microphone assembly 130, and the microphone assembly 140 in the clockwise direction. The microphones in each microphone assembly are sequentially defined as microphone 101, microphone 102, microphone 103, microphone 104, microphone 105, microphone 106, microphone 107, and microphone 108 in the order from the outer side of the base body 150 toward the center of the base body 150.

[0058] As shown Figure 4 , in this step, the compensation value of each microphone of the microphone array under various occlusion conditions obtained through testing includes the following sub-steps:

[0059] S101. Number each microphone in the test microphone array according to its position. Since the microphone array in this embodiment includes four microphone components, the microphone number can include both a group number and a number within the group, using "group number" + "number within the group" for microphone numbering. For example, the group number of microphone component 110 can be determined as 11, the group number of microphone component 120 as 12, the group number of microphone component 130 as 13, and the group number of microphone component 140 as 14. Set the number within the group of microphone 101 to 01, the number within the group of microphone 102 to 02, the number within the group of microphone 103 to 03, the number within the group of microphone 104 to 04, the number within the group of microphone 105 to 05, the number within the group of microphone 106 to 06, the number within the group of microphone 107 to 07, and the number within the group of microphone 108 to 08. That is, microphone 101 in microphone assembly 110 is numbered "1101", microphone 101 in microphone assembly 120 is numbered "1201", and so on, thereby assigning a unique number to each microphone in the microphone array.

[0060] S102. Test the microphone array under unobstructed conditions to obtain the signal strength of each numbered microphone under unobstructed conditions. By testing the signal strength of the microphones under unobstructed conditions, and using the signal strength of the microphones under unobstructed conditions as a benchmark, compensate accordingly for the microphone gain changes caused by various obstruction conditions.

[0061] S103. Record the relative positional relationship between each numbered microphone and the obstruction under various occlusion conditions, and test the microphone array to obtain the signal strength of each numbered microphone under various occlusion conditions. Specifically, one side of the base 150 can be taken as the positioning side, and the relative positional relationship between the positioning side and the obstruction, as well as the relative positional relationship between each numbered microphone and the positioning side, can be recorded. The following uses the first side 151 as the positioning side as an example to illustrate the five types of occlusion conditions.

[0062] An obstruction 201 is placed at the first side 151 (i.e., the positioning side) of the microphone array, thus creating a one-sided obstruction. At this time, the positional relationships between the second side 152, the third side 153, the fourth side 154, the microphone assembly 110, the microphone assembly 120, the microphone assembly 130, the microphone assembly 140, the obstruction 201, and the first side 151 are as follows: Figure 5 As shown.

[0063] Obstacles 201 and 202 are placed on the first side 151 (i.e., the positioning side) and the second side 152 of the microphone array, respectively, thus creating a situation where adjacent sides are obscured. At this time, the positional relationship between the second side 152, the third side 153, the fourth side 154, the microphone assembly 110, the microphone assembly 120, the microphone assembly 130, the microphone assembly 140, the obstacles 201 and 202, and the first side 151 is as follows: Figure 6 As shown.

[0064] Obstacles 203 and 202 are placed on the fourth side 154 and the second side 152 of the microphone array, respectively, thus creating a situation of relative obstruction on two sides. At this time, the positional relationships between the second side 152, the third side 153, the fourth side 154, the microphone assembly 110, the microphone assembly 120, the microphone assembly 130, the microphone assembly 140, the obstacles 203 and 202, and the first side 151 are as follows: Figure 7 As shown.

[0065] By placing obstructions 203, 201, and 202 on the fourth side 154, the first side 151, and the second side 152 of the microphone array, a three-sided obstruction is formed. At this time, the positional relationships between the second side 152, the third side 153, the fourth side 154, the microphone assembly 110, the microphone assembly 120, the microphone assembly 130, the microphone assembly 140, the obstructions 203, 201, and 202, and the first side 151 are as follows: Figure 8 As shown.

[0066] Obstacles are placed on the first side 151, the second side 152, the third side 153, and the fourth side 154 of the microphone array, thus creating a four-sided obstruction. Since the shape formed by the obstacles is also a rotationally symmetric shape with a rotation angle of 90°, there is only one positional relationship between the microphone assembly 110, microphone assembly 120, microphone assembly 130, microphone assembly 140, and the four obstacles.

[0067] S104. Subtract the signal strength of the microphone numbered under the unobstructed condition from the signal strength of the microphone numbered under each type of obstruction condition to obtain the compensation value of each microphone numbered under the five types of obstruction conditions: one-sided obstruction, two adjacent obstructions, two opposite obstructions, three-sided obstruction, and four-sided obstruction.

[0068] It should be noted that the microphone array used for testing is not necessarily the same as the microphone array installed later, meaning the compensation values ​​obtained from the test are universal. Furthermore, the numbering of each microphone in the microphone array during testing is only for recording the positional relationship between each microphone and the obstruction, and is not a fixed numbering system for the microphones. That is, the numbering indicates the positional relationship between the microphone and the obstruction; for the same microphone array, the microphone numbering will change accordingly when the obstruction is placed in different locations.

[0069] S2. After the microphone array is installed, the installation environment of the microphone array (i.e., the type of obstruction around the microphone array and the location of the obstruction) is identified. Infrared sensors can be installed on the four sides of the base 150 to identify whether there are obstacles on the four sides. When determining the type of obstruction, if an infrared sensor on one side detects an obstruction, it is determined to be one-sided obstruction; if infrared sensors on two sides detect an obstruction, it is further determined whether the two sides that detected the obstruction are adjacent. If they are adjacent, it is determined to be two-sided obstruction; otherwise, it is determined to be two-sided obstruction; if infrared sensors on three sides detect an obstruction, it is determined to be three-sided obstruction. When determining the location of the obstruction, the four sides of the base 150 can be divided into four directions: front, back, left, and right. Based on the detection results of the infrared sensors, it can be determined whether there are obstructions in the front, back, left, and right directions respectively.

[0070] S3. Based on the type and location of the occlusion, determine the compensation value for each microphone in the microphone array, and then compensate the gain of each microphone according to the compensation value. For example... Figure 9 As shown, this step may include the following sub-steps:

[0071] S301. Based on the identified occlusion type, occlusion location, and the recorded relative positional relationship between each microphone number and the occluder, determine the number of each microphone in the microphone array. At this point, first determine the positioning side of the microphone array base 150 based on the occlusion type and occlusion location, then determine the number of each microphone in the microphone array based on the relative positional relationship between each microphone number and the positioning side. For example: when the identified occlusion type is one-sided occlusion, and the occluder is on the left side of the microphone array, then the left side of the base 150 is the first side 151 (i.e., the positioning side). Figure 5 (Will Figure 5Rotating counterclockwise by 90 degrees (meaning the obstruction is on the left side of the microphone array) allows you to determine the positions of microphone components 110, 120, 130, and 140. At this point, the determined positions of the first side 151, second side 152, third side 153, fourth side 154, microphone components 110, 120, 130, 140, and the obstruction 201 are as follows: Figure 10 As shown, the group number of each microphone can be determined. Of course, in the case of four-sided obstruction, any side of the base 150 can be designated as the first side 151, thereby determining the positions of the second side 152, the third side 153, the fourth side 154, the microphone assembly 110, the microphone assembly 120, the microphone assembly 130, and the microphone assembly 140.

[0072] Since the four microphone components are arranged at 90° intervals, the group number of each microphone remains unchanged regardless of the microphone array's installation. Only the group number changes depending on the direction of the obstruction. For example, when the obstruction is located behind the microphone array, the microphone component in the rear left corner is microphone component 110; when the obstruction is located on the left side of the microphone array, the microphone component in the rear left corner becomes microphone component 120. That is, due to the different positions of the obstruction, the group number of the microphone component in the rear left corner changes from "11" to "12". However, microphone 101 remains "01" regardless of the group number change. Therefore, once the group number of each microphone is determined, the individual number of each microphone can be determined.

[0073] S302. Based on the identified occlusion type, the compensation value corresponding to each microphone number is obtained. Since the compensation value corresponding to each microphone number has already been obtained in S104, the compensation value corresponding to that microphone can be retrieved after determining the number of each microphone.

[0074] S303. Adjust the parameters of the microphone array according to the compensation value, and perform gain compensation for each numbered microphone to eliminate the influence of obstructions on the microphone array.

[0075] Since it is difficult to keep a microphone array perfectly horizontal during installation, and sometimes the microphone array is installed at an angle, while the microphone array is corrected for horizontal installation, in order to improve the accuracy of orientation recognition and signal capture when the microphone array is installed at an angle, compensation can be made for each microphone according to the tilt angle of the microphone array after installation. Specifically, this can include the following steps:

[0076] S910. Multiple sound source emission angles are pre-selected as correction angles, and the overall signal strength value of the audio signals collected by the microphone array at each correction angle is tested as the measurement value. During the test, the sound source is placed directly below the microphone array. The overall signal strength value is the signal strength value of the signals collected by all microphones in the microphone array (32 microphones in this embodiment) after fusion.

[0077] When selecting the sound source's emission angle as the correction angle, based on the variation of the microphone array's overall signal strength with the sound source's emission angle, the range where the microphone array's overall signal strength increases with the emission angle is divided into a linearly increasing range, and the range where the microphone array's overall signal strength decreases with the emission angle is divided into a linearly decreasing range. Analysis of the microphone array's test data revealed that when the sound source's emission angle is between 0° and 180°, the overall signal strength of the audio signal acquired by the microphone array increases linearly with the emission angle; conversely, when the sound source's emission angle is between 180° and 360°, the overall signal strength of the audio signal acquired by the microphone array decreases linearly with the emission angle. Therefore, the range of 0° to 180° is designated as the linearly increasing range, and the range of 180° to 360° is designated as the linearly decreasing range. Among them, a correction angle of 0° means that the sound source is emitting sound directly at the center of the microphone array; a correction angle of 180° means that the sound source is emitting sound away from the center of the microphone array; and a correction angle of 360° means that the sound source is emitting sound one full rotation and then returns to the direction that is emitting sound directly at the center of the microphone array.

[0078] Next, multiple angles are selected at equal intervals within the linearly increasing and decreasing intervals, and these angles, along with 0°, 180°, and 360°, are used as correction angles. For example, when 30° is used as the interval between the linearly increasing and decreasing intervals, the correction angles include 0°, 30°, 60°, 90°, 120°, 150°, 180°, 210°, 240°, 270°, 300°, 330°, and 360°. Of course, to improve compensation accuracy, smaller angle values ​​can be used for the intervals.

[0079] After obtaining the measured values ​​through testing, the overall signal strength value of the microphone array can be obtained as a function curve of the sound source's emission angle through data fitting. Based on the function curve, each measured value can be corrected so that the corrected measured values ​​are all located on the function curve, thereby eliminating measurement errors.

[0080] S920. Obtain the tilt angle of the microphone array after installation. An angle sensor can be installed on the microphone array, and the tilt angle of the microphone array after installation can be measured using the angle sensor.

[0081] S930. Based on the test values ​​obtained from pre-testing, calculate the tilt correction value corresponding to the tilt angle using a linear interpolation method, and perform gain compensation on the audio signal actually acquired by the microphone array based on the tilt correction value. This step may include the following sub-steps:

[0082] S931. Select the correction angle that is smaller than the tilt angle and closest to the tilt angle as the first interpolation angle; select the correction angle that is larger than the tilt angle and closest to the tilt angle as the second interpolation angle.

[0083] S932. Since the overall signal strength of the audio signal acquired by the microphone array is basically linearly related to the sound source's emitting angle within the linearly increasing and decreasing intervals, the theoretical signal strength value at this tilt angle can be calculated using the following formula:

[0084]

[0085] Where θ represents the tilt angle of the microphone array after installation, that is, the angle between the microphone array and the horizontal direction after installation; signal(θ) represents the theoretical signal strength value when the tilt angle is θ; a represents the first interpolation angle; b represents the second interpolation angle; val(a) represents the measured value corresponding to the first interpolation angle; val(b) represents the measured value corresponding to the second interpolation angle.

[0086] S933. The tilt correction value corresponding to a tilt angle of θ is calculated using the following formula:

[0087] signal(correction)=signal(0)-signal(θ)

[0088] Where signal(correction) represents the tilt correction value; signal(0) represents the measured value when the correction angle is 0°, which is the expected overall signal strength value.

[0089] S134. Perform gain compensation on the overall signal strength of the microphone array based on the tilt correction value; the gain compensation formula is as follows:

[0090] signal(compensation)=signal(measured)+signal(correction)

[0091] Here, signal(compensation) represents the overall signal strength value of the microphone array after gain compensation, and signal(measured) represents the overall signal strength value of the microphone array before gain compensation.

[0092] For example, when the tilt angle θ = 50°, 30° can be taken as the first interpolation angle and 60° as the second interpolation angle. Substituting the test values ​​corresponding to the correction angles of 30° and 60° into the above formula, the tilt correction value signal(correction) can be obtained. This increases the overall signal strength value of the microphone array by signal(correction), thus completing the tilt angle compensation of the microphone array.

[0093] In this embodiment, by pre-testing the compensation value of each microphone in the microphone array under various obstruction conditions, the gain of each microphone can be compensated according to the installation environment. This significantly reduces the impact of obstructions on the microphone array caused by different installation methods, avoiding negative impacts on the identification of sound source direction. Furthermore, by not fixing the microphone numbers before installation, and identifying the location of the obstruction after installation, and then determining the microphone numbers based on the location of the obstruction, compared to fixing microphone numbers, any side of the microphone array can be aligned with the obstruction during installation, eliminating the need to align a fixed side of the microphone array with the obstruction, thus making installation more flexible.

[0094] Example 2

[0095] like Figure 11 As shown, one preferred embodiment of the audio acquisition device of the present invention includes a microphone array, an audio processing unit, and an occlusion compensation unit. The microphone array is an array of multiple microphones arranged geometrically on a base 150; in this embodiment, the microphone array includes four microphone assemblies (110, 120, 130, 140) arranged at 90° intervals. Each microphone assembly includes eight microphones (101, 102, 103, 104, 105, 106, 107, 108) arranged linearly, thereby using 32 microphones to form an inclined "+" shape.

[0096] The audio processing unit is used to perform sound source localization and speech enhancement processing on the signals acquired by the microphone array. The audio processing unit may include a preprocessing module, a sound source localization module, a speech enhancement module, and an output module. The preprocessing module is used to preprocess the signals acquired by the microphone array, including filtering, gain control, and noise cancellation. The sound source localization module is used to identify the direction and distance of the sound source based on the signals acquired by the microphone array; algorithms such as beamforming or Gaussian mixture models can be used for sound source direction and distance identification. The speech enhancement module is used to effectively form a beam in the desired direction using beamforming technology, picking up only the signal within the beam, thereby achieving the purpose of simultaneously extracting the sound source and suppressing noise; and to improve the quality and reliability of the acquired speech signal by processing it; typically, techniques including noise reduction, echo suppression, and sound enhancement are used to process the speech signal. The output module is used to output the signal processed by the speech enhancement module to subsequent audio processing devices or embedded systems.

[0097] The occlusion compensation unit is used to compensate the gain of each microphone in the microphone array using the occlusion compensation method of the microphone array in Embodiment 1. The occlusion compensation unit may include a compensation value storage module, an occlusion condition recognition module, and an adaptive algorithm module. The compensation value storage module stores the compensation value of each microphone in the microphone array under various occlusion conditions, obtained through testing. The compensation value can be obtained through step S1 in Embodiment 1. The occlusion condition recognition module is used to identify the occlusion conditions around the microphone array and the location of the occluding objects. Infrared sensors can be used to collect the location information of the occluding objects around the microphone array, and the occlusion conditions and the location of the occluding objects can be identified based on the location information. Alternatively, other methods can be used to identify the occlusion conditions and the location of the occluding objects around the microphone array. The occlusion condition recognition module executes step S2 in Embodiment 1. The adaptive algorithm module derives the compensation value corresponding to each microphone in the microphone array based on the occlusion condition and the occlusion location, and causes the audio processing unit to compensate the gain of each microphone in the microphone array according to the compensation value. The occlusion recognition module is used to execute step S3 in embodiment 1, so as to adaptively adjust the signal processing algorithm parameters of the audio processing unit according to the state of the microphone array and environmental conditions.

[0098] The audio acquisition device in this embodiment can perform gain compensation for each microphone in the microphone array according to the installation environment, thereby greatly reducing the impact of obstructions on the microphone array, avoiding negative impacts on the identification of sound source direction, and improving the reception effect and accuracy of the microphone array. Furthermore, during installation, any side of the microphone array can be aligned with an obstruction, eliminating the need to align a fixed side of the microphone array with an obstruction. After installation, the device can automatically identify the location of the obstruction and determine the microphone number, making installation more flexible compared to methods with fixed microphone numbers.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for compensating for occlusion in a microphone array, characterized in that, Includes the following steps: S1. Classify the occlusion conditions of the microphone array in advance; and obtain the compensation value of each microphone in the microphone array under various occlusion conditions through testing; S2. After the microphone array is installed, identify the type of obstruction around the microphone array and the location of the obstruction. S3. Based on the type and location of the occlusion, obtain the compensation value for each microphone in the microphone array, and compensate the microphone gain according to the compensation value. In step S1, determining the compensation value for each microphone in the microphone array under various occlusion conditions through testing includes the following sub-steps: S101. Number each microphone in the test microphone array according to its position; S102. Test the microphone array under unobstructed conditions to obtain the signal strength of each numbered microphone under unobstructed conditions; S103. Record the relative positional relationship between each numbered microphone and the obstruction under various obstruction conditions, and test the microphone array to obtain the signal strength of each numbered microphone under various obstruction conditions. S104. Subtract the signal strength of the microphone numbered under the unobstructed condition from the signal strength of the microphone numbered under each type of obstruction condition to obtain the compensation value of the microphone numbered under each type of obstruction condition. Step S3 includes the following sub-steps: S301. Based on the identified type of occlusion, the occlusion location, and the relative position of each microphone number to the occlusion object, determine the number of each microphone in the microphone array. S302. Based on the identified occlusion type, determine the compensation value corresponding to each microphone number. S303. Perform gain compensation on each microphone numbered according to the compensation value.

2. The occlusion compensation method for a microphone array according to claim 1, characterized in that: The microphone array includes a base and multiple microphones mounted on the base. The base is a regular polygon, and the multiple microphones are arranged to form a rotationally symmetric figure, wherein the rotation angle of the rotationally symmetric figure is equal to the exterior angle of the regular polygon.

3. The occlusion compensation method for a microphone array according to claim 2, characterized in that: In step S103, one side of the seat is taken as the positioning side, and the relative positional relationship between the positioning side and the obstruction and the relative positional relationship between each numbered microphone and the positioning side are recorded. In step S301, the positioning side of the microphone array base is first determined according to the occlusion situation and occlusion direction, and then the number of each microphone in the microphone array is determined according to the relative position relationship between each numbered microphone and the positioning side.

4. The occlusion compensation method for a microphone array according to claim 2 or 3, characterized in that: The base is square, and the rotation angle of the rotationally symmetrical figure formed by the arrangement of the multiple microphones is equal to 90°; the occlusion of the microphone array is classified into one-sided occlusion, adjacent two-sided occlusion, opposite two-sided occlusion, three-sided occlusion, and four-sided occlusion.

5. An audio acquisition device, characterized in that: include A microphone array, wherein the microphone array is an array of multiple microphones arranged geometrically on a base; The audio processing unit is used to perform sound source localization and speech enhancement processing on the signals acquired by the microphone array; as well as An occlusion compensation unit is used to compensate the gain of each microphone in the microphone array using the occlusion compensation method of the microphone array as described in any one of claims 1 to 4.

6. The audio acquisition device according to claim 5, characterized in that: The audio processing unit includes The preprocessing module is used to preprocess the signals acquired by the microphone array; The sound source localization module is used to identify the direction and distance of the sound source based on the signals collected by the microphone array; The speech enhancement module is used to form a beam in the desired direction using beamforming technology, thereby extracting the sound source and suppressing noise; and to process the acquired speech signal to improve the quality and reliability of the speech. as well as The output module is used to output the signal processed by the voice enhancement module to subsequent audio processing devices or embedded systems.

7. The audio acquisition device according to claim 5, characterized in that: The occlusion compensation unit includes The compensation value storage module is used to store the compensation value of each microphone in the microphone array under various occlusion conditions; The occlusion recognition module is used to identify the occlusion around the microphone array and the location of the obstruction. as well as The adaptive algorithm module is used to determine the compensation value for each microphone in the microphone array based on the occlusion situation and occlusion direction, and to enable the audio processing unit to compensate the gain of each microphone in the microphone array according to the compensation value.

8. The audio acquisition device according to claim 7, characterized in that: The occlusion recognition module uses an infrared sensor to collect the location information of obstructions around the microphone array, and identifies the occlusion around the microphone array and the location of the obstructions based on the location information.

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