A signal processing method and device of a three-dimensional integrated MEMS acoustic vector sensor

Abstract

The application discloses a signal processing method and device of a three-dimensional integrated MEMS sound vector sensor, and belongs to the technical field of sound signals in a three-dimensional space. The application utilizes MEMS sound vector sensitive chips placed on two pairs of parallel corresponding sides, the sensitive directions of the four MEMS sound vector sensitive chips and the horizontal direction can be any angle, and the sound signal distribution in the three-dimensional space is obtained by solving the four vector velocity signals. Compared with a traditional orthogonal structure, the application can reduce the directional asymmetry problem caused by the MEMS sound vector sensitive chips not sharing a point, reduce the asymmetry of the axial sensitivity, and provide the possibility of the point correction of the back end. In addition, because the MEMS sound vector sensitive chips can be placed at any angle, the problem caused by the chip placement angle error during assembly can be reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sound signal in three-dimensional space, and particularly relates to a signal processing method and device of a three-dimensional integrated MEMS sound vector sensor. BACKGROUND

[0002] The sound vector sensitive chip generally refers to a sensor capable of measuring the sound particle vibration velocity information at a single point. The sound vector sensitive chip has differential pressure type, same vibration type, MEMS cilium type and MEMS thermal type sound vector sensors. The conventional differential pressure type, same vibration type and MEMS cilium type sound vector sensitive chips cannot directly measure the sound particle vibration velocity, which is a basic physical quantity. The MEMS thermal type sound vector sensitive chip measures the temperature change of the temperature measuring beam at different directions to obtain the vector information of sound, thereby directly measuring the sound particle vibration velocity.

[0003] Generally, the MEMS thermal type sound vector sensitive chip measures the sound particle vibration velocity signal along a single axis, that is, a one-dimensional vibration velocity component is obtained. The MEMS sound vector sensor generally refers to a sensor integrated with a standard sound pressure sensor and a sound vector sensitive chip.

[0004] The three-dimensional sound vector sensor refers to a sensor capable of simultaneously obtaining the sound pressure and the vibration velocity component information in the X, Y and Z three-axis directions, which is composed of a standard sound pressure sensor and multiple MEMS sound vector sensitive chips.

[0005] The typical three-dimensional sound vector sensor is composed of a standard sound pressure sensor and three mutually perpendicular orthogonal MEMS sound vector sensitive chips, that is, a conventional orthogonal structure is adopted. In this structure, the horizontal direction and the vertical direction may be different. In addition, the sensitive directions of the three orthogonal MEMS sound vector sensitive chips placed in this structure are not completely coplanar, which brings the inconsistency of the signal quantities obtained by the three axes, and the asymmetry of the directivity due to the position of the MEMS sound vector sensitive chip from the side. SUMMARY

[0006] In view of the problems in the prior art, the present application provides a signal processing method and device of a three-dimensional integrated MEMS sound vector sensor.

[0007] The technical scheme provided by the present application is as follows:

[0008] A signal processing method of a three-dimensional integrated MEMS sound vector sensor, the steps of which comprise:

[0009] 1) four MEMS sound vector sensitive chips are arranged on two pairs of parallel corresponding sides, the two pairs of parallel corresponding sides are perpendicular to each other, wherein the angle between the sensitive direction on the sensitive plane of the MEMS sound vector sensitive chip on each side and the horizontal direction is b1, b2, b3, b4, respectively, and each is an arbitrary angle;

[0010] 2) the vibration velocity signals V1 and V3 of the two MEMS sound vector sensitive chips on a pair of parallel sides are obtained, and the vibration velocity signals V2 and V4 of the two MEMS sound vector sensitive chips on another pair of parallel sides are obtained, and the sound particle vibration velocity signal components in the Y-axis and Z-axis directions are calculated according to the following formula:

[0011]

[0012] A three-dimensional integrated MEMS sound vector sensor, characterized in that it comprises a column, a MEMS sound vector integrated module and a signal acquisition and processing system, wherein the MEMS sound vector integrated module comprises a sound pressure sensor and four MEMS sound vector sensitive chips, the four MEMS sound vector sensitive chips are arranged on two pairs of parallel sides of the column which are perpendicular to each other, the MEMS sound vector integrated module simultaneously obtains the sound pressure and the vibration velocity signals of the four MEMS sound vector sensitive chips, the signal acquisition and processing system is used for collecting and calculating the vibration velocity signals of the four MEMS sound vector sensitive chips, and sound particle vibration velocity signal components in the X-axis, Y-axis and Z-axis directions are obtained.

[0013] A protective shell is arranged on the MEMS sound vector sensitive chip to protect the MEMS sound vector sensor.

[0014] The cross section of the column can be rectangular, square or regular octagonal, and the column comprises two groups of perpendicular planes.

[0015] A signal conditioning circuit is arranged in the MEMS sound vector sensitive chip integrated module, and the signal conditioning circuit is used for amplifying and filtering the signals output by the four MEMS sound vector sensitive chips and the standard sound pressure sensor.

[0016] The beneficial effects of the application are as follows:

[0017] The application utilizes MEMS sound vector sensitive chips placed on two pairs of parallel corresponding sides, the sensitive direction and horizontal direction of the four MEMS sound vector sensitive chips can be any angle, and the sound signal distribution in three-dimensional space is obtained by solving the four vector vibration speed signals. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a MEMS sound vector sensitive chip integrated module of the application; wherein, 1-MEMS sound vector sensitive chip; 2-sound pressure sensor; 3-protection shell; 4-column; 5-signal conditioning circuit;

[0019] Figure 2 It is a MEMS sound vector sensitive chip integrated module of the application; wherein, 1-MEMS sound vector sensitive chip; 2-sound pressure sensor; 3-protection shell; 4-column; 5-signal conditioning circuit;

[0020] Figure 3 It is a MEMS sound vector sensitive chip integrated module of the application; wherein, 1-MEMS sound vector sensitive chip; 2-sound pressure sensor; 3-protection shell; 4-column; 5-signal conditioning circuit;

[0021] Figure 4 It is a MEMS sound vector sensitive chip integrated module of the application; wherein, 1-MEMS sound vector sensitive chip; 2-sound pressure sensor; 3-protection shell; 4-column; 5-signal conditioning circuit; DETAILED DESCRIPTION

[0022] The application will be further described below by combining with the embodiments and the drawings.

[0023] The three-dimensional integrated MEMS sound vector sensor provided by the application comprises a MEMS sound vector sensitive chip integrated module, a rectangular column and a signal acquisition and processing system.

[0024] As shown in Figure 1 The MEMS sound vector sensitive chip integrated module comprises a sound pressure sensor and four MEMS sound vector sensitive chips, the four MEMS sound vector sensitive chips are arranged on the four sides of the rectangular column respectively, the sound pressure sensor is arranged on the top plane of the rectangular column, two MEMS sound vector sensitive chips are placed on each pair of parallel sides, and the sensitive direction of the MEMS sound vector sensitive chip is obliquely upward or downward along the side of the rectangular column. Figure 2As shown, the four MEMS sound vector sensitive chips can be placed at any angle within the range of 0°-90°, the angle between the sensitive direction of the MEMS sound vector sensitive chip on the mutually parallel two faces and the horizontal direction on the respective sensitive plane is any angle, that is, there are two groups of MEMS sound vector sensitive chips with different angle distribution between the sensitive direction and the horizontal direction, and the protective shell is placed on the four MEMS sound vector sensors to protect the MEMS sound vector sensors.

[0025] The signal conditioning circuit is arranged in the MEMS sound vector sensitive chip integrated module, and is used for amplifying and filtering the signals output by the four MEMS sound vector sensitive chips and the standard sound pressure sensor.

[0026] Reference Figure 3 The MEMS sound vector sensitive chip is placed on the two symmetrical faces of the rectangular column body at any angle, the four-way vector velocity signals obtained by the MEMS sound vector sensitive chip integrated module and the signal of the sound pressure sensor, the signals of the above four MEMS sound vector sensitive chips and the sound pressure sensor are output to the signal acquisition and processing system after passing through the signal conditioning circuit, the signal acquisition and processing system includes a signal acquisition module, a signal processing module and a signal output module, and is used for acquiring and calculating the velocity signals of the two MEMS sound vector sensitive chips on the two corresponding parallel sides, and obtaining the sound particle velocity signal components in the X-axis, Y-axis and Z-axis directions.

[0027] The vector velocity signals of the four MEMS sound vector sensitive chips are acquired, and the four-way vector velocity signals are Figure 4 As shown. Among them, for the vector sound particle velocity signal v, the three axial components v x , v y , v z in the three-dimensional space satisfy the following formula:

[0028]

[0029] Among them, θ represents the horizontal deflection angle and the elevation angle of the velocity signal in the three-dimensional space.

[0030] As shown in Figure 4 (a), the component of the vector velocity signal v in the XOZ plane is v || , the component of the vector velocity signal v in the YOZ plane is v ⊥ , and the velocity components obtained by the four-way sensitive chip are v1, v2, v3 and v4. As shown in Figure 4 (b), the component of the velocity signal v in the XOZ plane is v ||The angle between the sensor and the x-axis is α. Taking the first sensitive chip v1 as an example, the angle between the sensitive direction and the horizontal direction on the sensitive plane, that is, the angle between the placement of the sensitive chip and the x-axis, is b1.

[0031] Taking a single MEMS acoustic vector sensor chip as an example, the various signal components of the acoustic signal within the sensing plane of the single chip are as follows: Figure 4 As shown in (b), where v || and v ⊥ If we consider the acoustic signal components on the XOZ and YOZ planes of the sensitive plane, then the velocity components of the four MEMS acoustic vector sensing chips in their respective sensitive directions should be:

[0032]

[0033] v || and v ⊥ Within its corresponding sensitive plane, there are components on two orthogonal direction axes, namely, the components of the X and Z (or X and Y) axes should be:

[0034]

[0035] Formulas 1.1 and 1.3 can be further transformed into:

[0036]

[0037] Combining formulas 1.2 and 1.4, we can obtain:

[0038]

[0039] Furthermore, the transformation yields:

[0040]

[0041] The acoustic particle velocity signal components obtained by two MEMS acoustic vector sensing chips with mutually perpendicular sensing directions can be further processed to obtain the acoustic particle velocity signal components in the X-axis and Z-axis directions.

[0042] Similarly, the MEMS acoustic vector sensing chip on the other parallel side obtains the acoustic particle velocity signal components in the Y-axis and Z-axis directions through formulas.

[0043]

[0044]

[0045] This allows us to obtain the signal components in three dimensions, namely the X, Y, and Z axes, as outputs, which can then be processed further to obtain the desired application.

[0046] Since the velocity components along the Z-axis can be calculated from both the XOZ and YOZ planes, theoretically their values ​​should be the same. However, in practical applications, factors such as assembly can cause errors that result in them not being completely identical. Therefore, in signal preprocessing, the two values ​​are averaged.

[0047]

[0048] In summary, the signal components in the three-dimensional directions, namely the X, Y, and Z axes, can be obtained as follows:

[0049]

[0050] The three-dimensional spatial velocity components obtained from signal preprocessing are used as output for further signal processing to obtain applications.

[0051] Finally, it should be noted that the purpose of disclosing the embodiments is to help further understand the present invention. However, those skilled in the art will understand that various substitutions and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the present invention should not be limited to the content disclosed in the embodiments, and the scope of protection of the present invention is defined by the claims.

Claims

1. A signal processing method for a three-dimensional integrated MEMS acoustic vector sensor, comprising the following steps: 1) Four MEMS acoustic vector sensing chips are respectively set on two pairs of parallel corresponding sides, which are perpendicular to each other. The angles between the sensing direction and the horizontal direction on the sensing plane of the MEMS acoustic vector sensing chip on each side are b1, b2, b3, and b4, which are all arbitrary angles. 2) Obtain the vibration velocity signals V1 and V3 of two MEMS acoustic vector sensing chips on a pair of parallel sides, and the vibration velocity signals V2 and V4 of two MEMS acoustic vector sensing chips on another parallel side. Calculate the acoustic particle vibration velocity signal components in the Y-axis and Z-axis directions respectively according to the following formula.

2. A three-dimensional integrated MEMS acoustic vector sensor, characterized in that, The system includes a column, a MEMS acoustic vector integration module, and a signal acquisition and processing system. The MEMS acoustic vector integration module includes a sound pressure sensor and four MEMS acoustic vector sensing chips. The four MEMS acoustic vector sensing chips are respectively set on two pairs of parallel sides that are perpendicular to each other on the column. The MEMS acoustic vector integration module simultaneously obtains the sound pressure and the vibration velocity signals of the four MEMS acoustic vector sensing chips. The signal acquisition and processing system is used to acquire and calculate the vibration velocity signals of the four MEMS acoustic vector sensing chips to obtain the acoustic particle vibration velocity signal components in the X-axis, Y-axis, and Z-axis directions.

3. The three-dimensional integrated MEMS acoustic vector sensor as described in claim 2, characterized in that, A signal conditioning module is added to the MEMS acoustic vector integration module to amplify and filter the signals output by the four MEMS acoustic vector sensing chips.

4. The three-dimensional integrated MEMS acoustic vector sensor as described in claim 2, characterized in that, The cross-section of the column is rectangular, square, or octagonal.

5. The three-dimensional integrated MEMS acoustic vector sensor as described in claim 2, characterized in that, A protective shell is placed on the MEMS acoustic vector sensing chip.

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