CN113108896B - Probe type microphone device and measuring method thereof - Google Patents
Probe type microphone device and measuring method thereof Download PDFInfo
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- CN113108896B CN113108896B CN202110367141.7A CN202110367141A CN113108896B CN 113108896 B CN113108896 B CN 113108896B CN 202110367141 A CN202110367141 A CN 202110367141A CN 113108896 B CN113108896 B CN 113108896B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H17/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/08—Mouthpieces; Microphones; Attachments therefor
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Abstract
The embodiment of the invention provides a probe type microphone device and a measuring method thereof. The first microphone is for receiving an acoustic signal. The probe has an acoustic signal inlet end and an acoustic signal outlet end, the probe forming a propagation channel for the acoustic signal and causing the acoustic signal to propagate in the form of a plane wave of a specific frequency. The first microphone is installed at the measuring section of the probe, and the measuring end of the first microphone is flush with the inner wall surface of the probe. The radial mode extraction can be carried out by using a small number of microphones, the interference of a flow field and an acoustic field is small, and the cost is reduced.
Description
Technical Field
The embodiment of the invention relates to the technical field of acoustic measurement, in particular to a probe type microphone device and a measuring method thereof.
Background
In designing a quiet turbofan aircraft engine, fan noise mode extraction is critical to understanding the noise generation mechanism, sound propagation characteristics, and passive/active noise control methods.
Currently, there are mainly two modal extraction methods:
1. the method is characterized in that a continuously rotating microphone target is adopted, microphones on the target are distributed along the radial direction, and the circumferential and radial modal content is calculated according to the sound pressure distribution measured on the axial plane of the pipeline. The rotating rake can complete data acquisition in a short time, and has the disadvantage that doppler shift associated with the circumferential mode m occurs, which has a great influence on the post-processing time.
2. And a circle of microphones are arranged on the pipe walls of the plurality of axial planes in a flush mode along the circumferential direction, and the modal content is calculated through spatial decomposition. Since the number of turns required is related to the number of radial modes present, a cylindrical pipe needs to have a certain axial length. If there is little change in the radial modal content within the measurement range, the radial component can be determined from the axial propagation component. The advantage of this approach is that the impact on the acoustic and flow fields is small, but the microphone array must be carefully designed to ensure that the analysis results are of high quality.
The existing modal extraction technology has the following defects:
1. continuous rotation microphone target technology to solve the doppler shift problem of the rotating acoustic mode, the rotation speed of the target must be an integer multiple of the rotation speed of the shaft, and the phases of the target and the shaft should be synchronized. The rake therefore requires a very precise drive and control system so that phase errors do not accumulate over the test period. In addition, the rake creates a choking effect on the flow path and the trailing track of the rake introduces external noise.
2. The axial wave numbers of different low-order radial modes of the same circumferential mode at high frequency are very close, so that the radial modes cannot be correctly distinguished by implicitly realizing the separation of different radial mode contents through analyzing the axial wave numbers by the circumferential microphone arrays on a plurality of axial planes.
3. Both methods require a certain number of microphones to obtain enough spatial points for calculation, and high-precision microphones are expensive.
Disclosure of Invention
In order to solve or alleviate at least one of the above technical problems, embodiments of the present invention provide a probe microphone apparatus and a measurement method thereof, which can perform radial mode extraction with a small number of microphones and have small interference with a flow field and an acoustic field, thereby reducing cost.
In one aspect of an embodiment of the present invention, a probe microphone apparatus includes a probe and a first microphone;
the first microphone is used for receiving an acoustic signal;
the probe is provided with an acoustic signal inlet end and an acoustic signal outlet end, forms a propagation channel of the acoustic signal and enables the acoustic signal to propagate in the form of plane waves with specific frequency;
the first microphone is installed at the measuring section of the probe, and the measuring end of the first microphone is flush with the inner wall surface of the probe.
In another aspect of an embodiment of the present invention, a method for measuring a probe microphone apparatus includes:
connecting the probe of the probe type microphone device with a short sound guide tube of a calibration device;
installing a second microphone on the long branch sound guide pipe of the calibration device at a position symmetrical to the sound signal inlet end;
providing an acoustic signal of a specific frequency at one end of a main sound tube of the calibration device; the acoustic signal propagates in the form of a plane wave in the main sound tube, the long branch sound guide tube, the short branch sound guide tube and the probe;
the first microphone receives an acoustic signal at the measuring section of the probe, and the second microphone receives an acoustic signal at the position, symmetrical to the acoustic signal inlet end, on the long branch sound guide pipe;
estimating a transfer function H12(f) of acoustic signals received by the first microphone and the second microphone;
and (3) changing the intensity of the provided acoustic signal, and inversely calculating the acoustic signal at the position symmetrical to the acoustic signal inlet end according to the acoustic signal at the measuring section of the probe and the transfer function H12(f) to judge whether the transfer function H12(f) meets the requirement.
According to the probe type microphone device and the measuring method thereof, the probe is adopted, and due to the property of plane waves, the amplitude of a transfer function between sound signals received by two microphones cannot be too large or too small. According to the symmetry, the sound signals collected by the microphones at the symmetrical positions of the probe sound signal inlet end and the microphones at the probe sound signal inlet end are the same, and the problem that the microphones cannot be installed at the probe sound signal inlet end is solved. According to the acoustic signal and the transfer function at the position of the probe measuring section, the acoustic signal at the probe acoustic signal inlet end can be accurately restored, and the calculation time is short. In the experiment, the sound signals of different space points can be obtained only by changing the position of the probe, so that the number of microphones required by the modal extraction technology is greatly reduced, and the cost is saved.
Drawings
The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the principles of the embodiments of the invention.
Fig. 1 is a first structural diagram of a probe microphone device according to an embodiment of the present invention.
Fig. 2 is a second structural diagram of a probe microphone device according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a microphone mounting base according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of a microphone according to an embodiment of the present invention.
Fig. 5 is a schematic structural diagram of a calibration apparatus according to an embodiment of the present invention.
Description of reference numerals:
1-a signal generation module; 2-main sound tube; 3-long sound guide tube; 4-short sound conducting tubes; 5-a probe; 51-a threaded through hole; 52-microphone mount; 521-a through hole; 6-a second microphone; 7-a first microphone; 8-a data acquisition and processing module; 9-a sound source; 10-a signal generator; 11-a sound absorption module; 12-plane wave.
Detailed Description
The embodiments of the present invention will be described in further detail with reference to the drawings and the following description. It should be understood that the detailed description and specific examples, while indicating the embodiments of the invention, are given by way of illustration only. It should be noted that, for convenience of description, only the portions related to the embodiments of the present invention are shown in the drawings.
It should be noted that, in the embodiments of the present invention, features in the embodiments may be combined with each other without conflict. Embodiments of the present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
In one aspect, the present invention provides a probe microphone and a measurement method thereof, which can accurately recover an acoustic signal at an inlet cross section (acoustic signal inlet end) of a probe according to an acoustic signal transfer function and an acoustic signal at a probe measurement cross section by using the properties of plane waves in a pipeline and the symmetry of a device. In the experiment, the sound signals of different space points can be obtained only by changing the position of the probe, the number of microphones required by the modal extraction technology is greatly reduced, the cost is saved, and the outer wall surface of the probe can be designed into shapes such as a wing shape and the like to reduce the interference to a flow field and a sound field.
According to an aspect of an embodiment of the present invention, there is provided a probe microphone apparatus including a probe 5 and a first microphone 7. The first microphone 7 is for receiving acoustic signals; as shown in fig. 1, the probe 5 has an acoustic signal inlet end and an acoustic signal outlet end, and the probe 5 forms a propagation channel of the acoustic signal and causes the acoustic signal to propagate in the form of a plane wave of a specific frequency. Wherein the first microphone 7 is installed at the measuring section of the probe 5, and the measuring end of the first microphone 7 is flush with the inner wall surface of the probe 5.
With the microphone device of the embodiment of the present invention, it is possible to propagate an acoustic signal in the form of a plane wave in the probe 5, and to measure the acoustic signal propagated in the probe 5 by the first microphone 7. Acoustic signals of different space points can be obtained by changing the position of the probe 5, radial mode extraction is performed by using a small number of microphones, interference on a flow field and an acoustic field is small, and cost is reduced.
In an embodiment of the present invention, the microphone device further includes a microphone mount 52; as shown in fig. 1, a side wall of the probe 5 at the measurement section is provided with a threaded through hole 51, and the microphone mounting seat 52 is threadedly mounted in the threaded through hole 51.
Further, as shown in fig. 3, an outer wall of the microphone mounting seat 52 is provided with an external thread, and the microphone mounting seat 52 is provided with a through hole 521 for fixing the first microphone 7. As shown in fig. 4, the first microphone 7 has a cylindrical structure, and can be inserted and fixed into the through hole 521 of the microphone mounting seat 52 through an O-ring.
In one embodiment of the present invention, the probe 5 is configured in a straight rod shape, and the cross section of the inner wall of the probe 5 is configured in a polygon shape. The cross section of the polygonal inner wall can ensure that the inner wall surface for mounting the microphone is a plane, so that the microphone is flush with the inner wall surface. The probe 5 is used to propagate acoustic signals in the form of plane waves from the entrance of the probe 5 to the other end of the probe 5. When the frequency of the acoustic signal is below the cut-off frequency of the probe 5, the acoustic wave can only propagate in the form of a plane wave in the probe 5. Preferably, the cross-section of the inner wall of the probe 5 is rectangular or square in shape. The long side of the inner wall cross-section of the probe 5 directly determines the applicable frequency range of the transfer function. For example, when the probe 5 is a square tube with a side length of 8mm, the frequency of the acoustic signal at the inlet section of the probe should not exceed 21250Hz by back calculation from the transfer function and the acoustic signal at the measurement section of the probe at this time. The shape of the inner wall cross-section of the probe 5 does not change with increasing length of the pipe, the shape of the outer wall cross-section of the probe 5 may change with increasing length of the pipe, and the outer wall cross-section may be of various shapes, such as circular, rectangular, square, airfoil, etc.
The applicable frequency range of the transfer function can be controlled by changing the long side of the inner wall cross section of the probe 5. When the probe 5 is a rectangular tube, the highest frequencies that can be calibrated are: f ═ c × min (1/Lx,1/Ly)/2, wherein: f is the highest frequency; c is the speed of sound; lx and Ly are two side lengths of the cross section of the inner wall of the long branch sound guide tube 3 and the probe 5.
In one embodiment of the invention, the distance of the measuring section of the probe 5 from the sound signal inlet end is not less than three times the maximum side length of the inner wall cross section of the probe. In order to avoid the influence of high-order modes occurring due to the right-angle turn of the acoustic signal after the connection with the calibration device.
In an embodiment of the present invention, as shown in fig. 2, the microphone apparatus further includes a sound absorption module 11, where the sound absorption module 11 is made of a sound absorption material and is disposed at the acoustic signal outlet end. The shape of the cross section of the sound absorption module 11 should match the shape of the cross section of the inner wall of the probe so that the sound absorption module 11 can be inserted to be closely attached to the inner wall of the probe 5. In order to improve the accuracy of the reduction of the acoustic signal at the probe entrance cross section, the transfer function is required to have a flat response amplitude. The sound absorption module 11 is used to reduce the orifice reflection, which may cause the amplitude of the transfer function to vary too much, affecting the measurement accuracy.
In another aspect of the embodiments of the present invention, a method for measuring a probe microphone device by using a calibration device includes:
step 1, connecting a probe 5 of the probe type microphone device of any one of the above embodiments with a short sound guide tube 4 of a calibration device. Referring to fig. 5, the calibration apparatus includes a signal generating module 1, a main sound guiding tube 2, a long sound guiding tube 3, a short sound guiding tube 4, and a data collecting and processing module 8.
And 2, mounting a second microphone 6 at a position symmetrical to the sound signal inlet end on the long sound guide tube 3 of the calibration device.
And 3, providing an acoustic signal with a specific frequency at one end of the main sound tube 2 of the calibration device. The acoustic signal propagates in the form of a plane wave 12 in the main sound tube 2, the long branch sound guide tube 3, the short branch sound guide tube 4 and the probe 5.
And 4, receiving the acoustic signal at the measuring section of the probe 5 by the first microphone 7, and receiving the acoustic signal at the symmetrical part of the long branch sound guide pipe 3 with the acoustic signal inlet end by the second microphone 6.
And 6, changing the intensity of the provided acoustic signal, inversely calculating the acoustic signal at the position symmetrical to the acoustic signal inlet end according to the acoustic signal at the measuring section of the probe and the transfer function H12(f), and judging whether the transfer function H12(f) meets the requirement.
The measuring method of the embodiment of the invention adopts the probe, and due to the property of the plane wave, the amplitude of the transfer function between the sound signals received by the two microphones is not too large or too small. According to the symmetry, the sound signals collected by the microphones at the symmetrical positions of the probe sound signal inlet end and the microphones at the probe sound signal inlet end are the same, and the problem that the microphones cannot be installed at the probe sound signal inlet end is solved. According to the acoustic signal and the transfer function at the position of the probe measuring section, the acoustic signal at the probe acoustic signal inlet end can be accurately restored, and the calculation time is short.
In one embodiment of the present invention, step 3, providing an acoustic signal of a specific frequency at one end of the main sound tube 2 of the calibration apparatus comprises:
a single-frequency signal or a broadband random signal with stationarity and ergodicity of each state is used as an excitation electric signal.
The excitation electrical signal is converted into a corresponding acoustic signal.
The signal generating module 1 is used for providing an electrical signal of a specific frequency, waveform and output level and converting the electrical signal into a corresponding acoustic signal. The signal generating module 1 may comprise a sound source 9 and a signal generator 10. Wherein the signal generator 10 is used to generate an electrical signal of a specific frequency. The acoustic source 9 is arranged to generate a corresponding acoustic signal upon receiving an electrical signal at a particular frequency. The sound source 9 may be a speaker, and specifically, a speaker of a moving coil type (electrodynamic type), a capacitor type (electrostatic type), a piezoelectric type (crystal or ceramic type), an electromagnetic type (compression spring type), an ionic type, a pneumatic type, or the like may be used.
In one embodiment of the present invention, the step 5 of estimating the transfer function H12(f) of the acoustic signals received by the first microphone 7 and the second microphone 6 includes:
in step 51, the acoustic signal received by the second microphone 6 is p1(t), and the acoustic signal received by the first microphone 7 is p2(t), then: p2(t) ═ p1(t) × h12(t) (1);
where h12(t) is the transfer function of the second microphone 6 to the first microphone 7, which represents a linear convolution.
wherein P1(f) is the fourier transform of the acoustic signal received by the second microphone 6, P2(f) is the fourier transform of the acoustic signal received by the first microphone 7, and H12(f) is the transfer function between the acoustic signals received by the first microphone 7 and the second microphone 6. The transfer function H12(f) is obtained by the above equation (2). The random error caused by noise can be effectively inhibited by carrying out proper windowing and averaging processing on the complex sound pressure signal. P1(f), P2(f) and H12(f) are complex domain signals, have a real part and an imaginary part, and not only contain amplitude signals of different frequency points, but also include phase information of different frequency points.
The transfer function refers to a model for describing the relationship between the input and output of a linear system, which is an inherent transfer characteristic between the respective microphone positions under certain boundary conditions, independent of the excitation to which the system is subjected under linear conditions, and independent of the measurement instant. The input signal of the linear system can be obtained from the linear transfer function and the output signal of the linear system. In the present embodiment, the transfer function H12(f) refers to the frequency domain transfer relationship between the sound pressure signal p1(t) received from the first microphone 7 at the probe inlet cross section and the sound pressure signal p2(t) received from the second microphone 6 at the probe measurement cross section. When the relative position of the probe measurement cross section and the probe inlet cross section changes, the transfer function will change accordingly.
In an embodiment of the present invention, the measuring method further includes:
and 7, interchanging the positions of the first microphone 7 and the second microphone 6, and respectively measuring to obtain an acoustic signal transfer function H12(f) under the two installation conditions.
And 8, calculating the geometric mean value of the acoustic signal transfer function H12(f) obtained by two times of measurement, and taking the geometric mean value as the corrected transfer function.
In order to eliminate transfer function measurement errors caused by frequency response mismatch between the microphone and each channel of the measurement system as much as possible, the transfer function is corrected by adopting the microphone position interchange measurement method, namely, before formal measurement, the two microphones are normally installed and measured, then the two microphones are installed at the exchange positions and measured, and the acoustic signal transfer functions under the installation conditions are obtained by measurement twice respectively. And then calculating the geometric mean value of the acoustic signal transfer function obtained by two measurements, wherein the geometric mean value is the corrected transfer function.
In most acoustic environments, according to the acoustic signal at the probe measuring section and the transfer function H12(f), the acoustic signal at the probe inlet section can be accurately restored, the calculation time is short, and the method and the device have a very wide application prospect.
In summary, compared with the conventional method, the embodiment of the present invention has the following advantages:
(1) with the probe, due to the nature of plane waves, the amplitude of the transfer function between the acoustic signals received by the two microphones is neither too large nor too small, and if the orifice is not reflecting, the amplitude of the transfer function is 1.
(2) The symmetry is adopted, the sound signals collected by the microphones at the symmetrical positions of the cross section of the probe inlet are the same as the sound signals collected by the microphones at the cross section of the probe inlet, and the problem that the microphones cannot be installed at the cross section of the probe inlet is solved.
(3) The number of microphones required by the modal extraction technology is greatly reduced, and the cost is saved.
(4) The probe type microphone device is convenient to carry, simple to operate and easy to apply in engineering.
The calibration device is described in the following. As shown in fig. 5, the signal generating module 1 of the calibration apparatus is used for generating an electrical signal with a specific frequency and converting the electrical signal into a corresponding acoustic signal.
One end of the main sound tube 2 is connected with the signal generating module 1; the acoustic signal may propagate along the main sound tube 2. One end of the long branch sound guide pipe 3 is connected with the main sound guide pipe 2, and the sound signals transmitted in the main sound guide pipe 2 can be transferred to the long branch sound guide pipe 3 from the connection position of the two parts for transmission. The long sound guide tube 3 is provided with a plurality of standard microphone mounting holes for mounting standard microphones along the length direction. One end of the short branch sound guide tube 4 is connected with the main sound guide tube 2, and the other end is connected with one end of the probe 5. The sound signal propagating in the main sound guide tube 2 can be transferred to the short sound guide tube 4 from the joint of the short sound guide tube 4 for propagation, and then transferred to the probe 5 from the joint of the short sound guide tube 4 and the probe 5 for propagation. The main sound tube 2, the long branch sound guide tube 3, the short branch sound guide tube 4 and the probe 5 form a propagation channel of the acoustic signal, and each cause the acoustic signal to propagate in the form of a plane wave 12 of a specific frequency. That is, the main sound tube 2, the long branch sound guide tube 3, the short branch sound guide tube 4 and the probe 5 are each arranged so as to be able to define a propagation form of an acoustic signal therein, the acoustic signal being propagated only in the form of a plane wave 12 of a specific frequency, which is the same as the frequency of the electric signal.
The data acquisition and processing module 8 is connected with each mounted microphone and receives the output signal of each microphone.
The signal generating module 1 comprises a sound source 9 and a signal generator 10. The signal generator 10 is connected with a sound source 9, and the sound source 9 is connected with one end of the main sound tube 2; the signal generator 10 is used for generating an electric signal with a specific frequency, the sound source 9 is used for converting the electric signal with the specific frequency into a corresponding sound signal, and the sound source 9 can adopt a loudspeaker.
The cross sections of the inner walls of the main sound guide pipe 2, the long branch sound guide pipe 3 and the short branch sound guide pipe 4 are set to be polygonal. The joint of the main sound tube 2 and the long branch sound guide tube 3 and the joint of the main sound tube 2 and the short branch sound guide tube 4 are both positioned at the other end of the main sound tube 2. The position of the joint of the main sound tube 2 and the long branch sound guide tube 3 and the position of the joint of the main sound tube 2 and the short branch sound guide tube 4 are symmetrical about the axial direction of the main sound tube 2. The main sound tube 2 transmits the sound signal to the other end, and then the sound signal is transmitted into the long branch sound guide tube 3 and the short branch sound guide tube 4.
The axial direction of the main sound tube 2 is parallel to the propagation direction of the sound signals; the axial direction of the long branch sound guide pipe 3 and the axial direction of the short branch sound guide pipe 4 are both vertical to the axial direction of the main sound guide pipe 2; and the axial direction of the probe 5, the axial direction of the short branch sound guide tube 4 and the axial direction of the long branch sound guide tube 3 are collinear, so that the main sound guide tube 2, the long branch sound guide tube 3, the short branch sound guide tube 4 and the probe 5 are in the same vertical plane and are in an inverted T shape.
The cross sections of the inner walls of the long branch sound guide tube 3 and the probe 5 are rectangular, and the cross sections of the inner walls of the long branch sound guide tube and the probe are the same in size; so that the amplitude and phase of the acoustic signal propagating in both are the same. The maximum frequency of the electrical signal of a particular frequency is: f ═ c × min (1/Lx,1/Ly)/2, where: f is the maximum frequency; c is the speed of sound; lx and Ly are respectively the side lengths of the cross section of the inner wall. That is, the frequency of the microphone to be calibrated should not exceed the maximum frequency within which the acoustic signals can propagate in the form of plane waves 12, and if the acoustic signals above the maximum frequency have higher-order modes during propagation, the amplitude and phase of the acoustic signals collected by the microphones at different positions on the same cross section of the long branch sound guide tube 3 or the probe 5 are different, and it is possible that the amplitude at some positions is too small to make the measurement inaccurate, or the amplitude exceeds the microphone range too much.
In the description herein, reference to the description of the terms "one embodiment/mode," "some embodiments/modes," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/mode or example is included in at least one embodiment/mode or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed 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 at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless explicitly specified otherwise.
It should be understood by those skilled in the art that the foregoing embodiments are merely for illustrating the embodiments of the present invention clearly and are not intended to limit the scope of the embodiments of the present invention. Other variations or modifications will occur to those skilled in the art based on the foregoing disclosure and are within the scope of the embodiments of the invention.
Claims (10)
1. A probe type microphone device is characterized by comprising a probe and a first microphone;
the first microphone is used for receiving an acoustic signal;
the probe is provided with an acoustic signal inlet end and an acoustic signal outlet end, forms a propagation channel of the acoustic signal and enables the acoustic signal to propagate in the form of plane waves with specific frequency;
the first microphone is installed at the measuring section of the probe, and the measuring end of the first microphone is flush with the inner wall surface of the probe;
the probe is connected with a short sound guide tube of the calibration device;
a second microphone is arranged on the long branch sound guide pipe of the calibration device at a position symmetrical to the sound signal inlet end;
providing an acoustic signal of a specific frequency at one end of a main sound tube of the calibration device; the acoustic signal propagates in the form of a plane wave in the main sound tube, the long branch sound guide tube, the short branch sound guide tube and the probe;
the position of the joint of the main sound tube and the long branch sound guide tube and the position of the joint of the main sound tube and the short branch sound guide tube are axially symmetrical about the main sound tube;
the axial direction of the probe, the axial direction of the short branch sound guide tube and the axial direction of the long branch sound guide tube are collinear;
the first microphone receives the sound signal at the measuring section of the probe, and the second microphone receives the sound signal at the position on the long branch sound guide pipe, which is symmetrical to the sound signal inlet end.
2. The probe microphone apparatus of claim 1, further comprising a microphone mount; the lateral wall of the measuring section of the probe is provided with a threaded through hole, and the microphone mounting seat is mounted in the threaded through hole through threads.
3. The probe microphone device as claimed in claim 2, wherein the outer wall of the microphone mounting base is provided with an external thread, and the microphone mounting base is provided with a through hole for fixing the first microphone.
4. The probe microphone device as claimed in claim 1, wherein the probe is provided in a straight bar shape, and a cross section of an inner wall of the probe is provided in a polygonal shape.
5. The probe microphone apparatus as claimed in claim 4, wherein the distance of the measuring section of the probe from the acoustic signal entrance end is not less than three times the maximum side length of the inner wall cross section of the probe.
6. The probe microphone apparatus of claim 1, further comprising a sound absorption module made of a sound absorption material and disposed at the acoustic signal outlet end.
7. A method of measuring a probe microphone device, comprising:
connecting the probe of the probe microphone device according to any one of claims 1 to 6 with a short sound guide tube of a calibration device;
installing a second microphone on the long branch sound guide pipe of the calibration device at a position symmetrical to the sound signal inlet end;
providing an acoustic signal of a specific frequency at one end of a main sound tube of the calibration device; the acoustic signal propagates in the form of a plane wave in the main sound tube, the long branch sound guide tube, the short branch sound guide tube and the probe;
the first microphone receives an acoustic signal at the measuring section of the probe, and the second microphone receives an acoustic signal at the position, symmetrical to the acoustic signal inlet end, on the long branch sound guide pipe;
estimating a transfer function of acoustic signals received by the first microphone and the second microphone;
and changing the intensity of the provided acoustic signal, and inversely calculating the acoustic signal at the symmetrical position of the acoustic signal inlet end according to the acoustic signal at the measuring section of the probe and the transfer function to judge whether the transfer function meets the requirement.
8. The method of claim 7, wherein the providing an acoustic signal of a specific frequency at one end of a main sound tube of the calibration device comprises:
adopting a single-frequency signal or a broadband random signal with stationarity and ergodicity of each state as an excitation electric signal;
the excitation electrical signal is converted into a corresponding acoustic signal.
9. The method of claim 7, wherein the estimating a transfer function of the acoustic signals received by the first microphone and the second microphone comprises:
the acoustic signal received by the second microphone is p1(t), the acoustic signal received by the first microphone is p2(t), then: p2(t) ═ p1(t) × h12 (t); wherein h12(t) is the transfer function of the second microphone to the first microphone, representing a linear convolution;
performing fourier transform on the acoustic signals received by the first microphone and the second microphone to obtain: p2(f) ═ P1(f) · H12 (f); wherein P1(f) is a Fourier transform of the acoustic signal received by the second microphone, P2(f) is a Fourier transform of the acoustic signal received by the first microphone, and H12(f) is a transfer function between the acoustic signals received by the first and second microphones.
10. The method of measuring a probe microphone apparatus according to claim 7, further comprising:
exchanging positions of the first microphone and the second microphone and measuring the positions of the first microphone and the second microphone respectively to obtain acoustic signal transfer functions under the condition of two times of installation;
and calculating the geometric mean value of the acoustic signal transfer function obtained by two times of measurement, and taking the geometric mean value as the corrected transfer function.
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| CN115103287B (en) * | 2022-06-16 | 2023-06-20 | 北京航空航天大学 | Calibrating device and calibrating method for probe microphone |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101895809A (en) * | 2010-07-01 | 2010-11-24 | 北京航空航天大学 | Microphone calibrator and calibration method thereof |
| CN106921928A (en) * | 2017-04-06 | 2017-07-04 | 中国商用飞机有限责任公司北京民用飞机技术研究中心 | Measurement, calibration method and device to microphone |
| JP2019095255A (en) * | 2017-11-21 | 2019-06-20 | 岡山県 | Vertical incident sound absorption rate measuring device and vertical incident sound absorption rate measurement method |
| CN109916609A (en) * | 2019-03-20 | 2019-06-21 | 武汉理工大学 | A kind of modification method and device of built-up sound source noise signal |
| JP2020134524A (en) * | 2019-02-15 | 2020-08-31 | 岡山県 | Device and method for measuring vertical incidence sound absorption coefficient |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8824692B2 (en) * | 2011-04-20 | 2014-09-02 | Vocollect, Inc. | Self calibrating multi-element dipole microphone |
| KR101515615B1 (en) * | 2013-10-10 | 2015-05-06 | 한국표준과학연구원 | microphone probe and acoustic measurement apparatus used the same |
| CN204539472U (en) * | 2015-04-15 | 2015-08-05 | 中国计量学院 | A kind of microphones sensitivity measure system of method based on the comparison |
| CN111510842B (en) * | 2020-04-17 | 2021-08-10 | 北京百度网讯科技有限公司 | Microphone testing system and testing method |
-
2021
- 2021-04-06 CN CN202110367141.7A patent/CN113108896B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101895809A (en) * | 2010-07-01 | 2010-11-24 | 北京航空航天大学 | Microphone calibrator and calibration method thereof |
| CN106921928A (en) * | 2017-04-06 | 2017-07-04 | 中国商用飞机有限责任公司北京民用飞机技术研究中心 | Measurement, calibration method and device to microphone |
| JP2019095255A (en) * | 2017-11-21 | 2019-06-20 | 岡山県 | Vertical incident sound absorption rate measuring device and vertical incident sound absorption rate measurement method |
| JP2020134524A (en) * | 2019-02-15 | 2020-08-31 | 岡山県 | Device and method for measuring vertical incidence sound absorption coefficient |
| CN109916609A (en) * | 2019-03-20 | 2019-06-21 | 武汉理工大学 | A kind of modification method and device of built-up sound source noise signal |
Non-Patent Citations (2)
| Title |
|---|
| Asynchronous microphone arrays calibration and sound source tracking;Daobilige Su 等;《Autonomous Robots》;20200131;第44卷(第2期);第183-204页 * |
| 声源定位系统动态校准方法研究;张炳毅 等;《计测技术》;20190531;第39卷(第05期);第51-54页 * |
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