WO2019189484A1 - Microphone array and acoustic analysis system - Google Patents

Microphone array and acoustic analysis system Download PDF

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Publication number
WO2019189484A1
WO2019189484A1 PCT/JP2019/013396 JP2019013396W WO2019189484A1 WO 2019189484 A1 WO2019189484 A1 WO 2019189484A1 JP 2019013396 W JP2019013396 W JP 2019013396W WO 2019189484 A1 WO2019189484 A1 WO 2019189484A1
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WO
WIPO (PCT)
Prior art keywords
microphone
support
microphone array
mems
microphones
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PCT/JP2019/013396
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French (fr)
Japanese (ja)
Inventor
拓也 高橋
直穂子 豊嶋
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日本電産株式会社
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Priority to CN201980022562.7A priority Critical patent/CN111919454B/en
Publication of WO2019189484A1 publication Critical patent/WO2019189484A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B7/00—Microstructural systems; Auxiliary parts of microstructural devices or systems
    • B81B7/02—Microstructural systems; Auxiliary parts of microstructural devices or systems containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS]
    • 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
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K15/00—Acoustics not otherwise provided for
    • 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
    • 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
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones

Definitions

  • the present invention relates to a microphone array and an acoustic analysis system.
  • Patent Document 1 discloses a sound pressure distribution analysis system using a microphone array in which a plurality of microphones are arranged in a lattice pattern and sounds are detected at a plurality of positions.
  • This sound pressure distribution analysis system includes an amplifier capable of amplifying a multi-channel signal, and the amplifier amplifies each sound signal of the microphone and outputs it to the analysis terminal.
  • the analysis terminal A / D converts the sound signal input from the amplifier and records it as a time waveform.
  • a condenser microphone or a dynamic microphone is used. If the microphones are arranged at intervals of 1 cm or less, for example, the measurement surface of the microphone array becomes a dense structure, and the influence of reflected sound from the microphone array This makes it difficult to analyze acoustic holography. Therefore, a microphone array using a small MEMS (Micro-Electrical-Mechanical Systems) microphone that can be surface-mounted on a substrate is known. As such a MEMS microphone array, a method is known in which a plurality of MEMS microphones are surface-mounted on a lattice-shaped substrate, and the microphone array is configured by the substrate itself.
  • MEMS Micro-Electrical-Mechanical Systems
  • an object of the present invention is to provide a microphone array and an acoustic analysis system that can easily exchange a plurality of MEMS microphones in individual units.
  • a microphone array includes a plurality of MEMS microphones, a plurality of microphone boards each having the plurality of MEMS microphones mounted thereon, and a plurality of microphone boards. And a support member that detachably supports each of them.
  • an acoustic analysis system includes an acoustic analysis device that analyzes a signal input from each of the plurality of MEMS microphones and detects a physical quantity representing a feature of sound.
  • the plurality of MEMS microphones can be easily replaced in individual units.
  • FIG. 1 is an overall view of a microphone array in the present embodiment.
  • FIG. 2 is a diagram illustrating a configuration of the microphone.
  • FIG. 3 is a diagram showing the configuration of the first support.
  • FIG. 4 is a diagram showing the configuration of the second support.
  • FIG. 5 is a diagram illustrating an example of connection between the microphone and the control board.
  • FIG. 6 is a diagram illustrating an example of an acoustic analysis system.
  • FIG. 1 is an overall view of a microphone array 1 in the present embodiment.
  • the microphone array 1 in the present embodiment can be used in an acoustic analysis system that analyzes a sound to be measured from an object to be measured (sound source) using a near-field acoustic holography method.
  • a near-field acoustic holography method it is necessary to measure the sound pressure distribution on a measurement surface that is close to and parallel to the sound source surface, and a microphone array in which a plurality of microphones are arranged in a lattice shape is used.
  • the microphone array 1 includes a plurality of first supports 10, a plurality of second supports 20, and a plurality of microphones mc.
  • Each of the plurality of microphones mc is a MEMS (Micro-Electrical-Mechanical Systems) microphone.
  • the 1st support body 10 is a member which makes a 1st direction (x direction) a longitudinal direction, respectively.
  • the microphone array 1 includes M (eight in FIG. 1) first supports 10.
  • the 2nd support body 20 is a member which makes the 2nd direction (z direction) orthogonal to a 1st direction (x direction) a longitudinal direction, respectively.
  • the microphone array 1 includes two second supports 20. The two second supports 20 detachably support both ends of the M first supports 10.
  • the first support 10 supports N (eight in FIG. 1) microphones mc arranged at a constant interval d in the x direction. Moreover, the 1st support body 10 is arranged in parallel by the fixed space
  • the xz plane is a plane parallel to the measurement surface on which the microphones mc of the microphone array 1 are arranged in a grid, and is a plane parallel to the sound source surface of the object to be measured.
  • the microphone array 1 is arranged in a state where the measurement surface is separated from the sound source surface of the object to be measured by a predetermined distance in the y direction.
  • the microphone array 1 is arranged such that the distance between the measurement surface and the sound source surface in the y direction is within 1 cm.
  • the first support member 10 and the second support member 20 constitute a support member that supports the plurality of microphones mc.
  • the said supporting member is not limited to the structure shown in FIG.
  • the support member may include a plurality of first supports 10 and at least one second support 20.
  • the second support 20 may support only one end of the first support 10 or may support a position other than the end of the first support 10.
  • the microphone mc is an omnidirectional MEMS microphone capable of collecting sound from all directions. As shown in FIG. 2, the microphone mc incorporates an acoustic transducer (MEMS chip) using an MEMS technology and an amplifier, and is mounted on the surface of a microphone substrate 31 which is a small substrate.
  • the microphone mc converts sound (sound pressure) into an electrical signal using an acoustic transducer, amplifies the converted electrical signal using an amplifier, and outputs the amplified signal.
  • the microphone mc is a digital microphone
  • the microphone mc further includes an A / D converter, and can convert an analog signal amplified by an amplifier into a digital signal and output the digital signal.
  • each of the plurality of microphones mc is mounted on each independent microphone substrate 31, and the support member detachably supports each of the plurality of microphone substrates 31.
  • the M first supports 10 each support N microphone substrates 31 at a constant interval d in the x direction.
  • Each microphone substrate 31 is detachably attached to the first support 10 through an attachment hole 31 a formed in the microphone substrate 31.
  • the microphone board 31 is provided with a connector portion 32.
  • the connector part 32 is connected to a connector part 41a of a cable 41 for connecting the microphone mc and a control board 40 (see FIG. 5) for controlling the microphone mc. That is, the microphone mc is connected to the control board 40 via the cable 41.
  • FIG. 3 is a configuration diagram showing a part of the first support 10 in the present embodiment. 3 shows a state where the cable 41 and the connector part 41a in FIG.
  • the first support 10 includes a plurality of mounting holes 11 that can mount the microphone substrate 31 at an arbitrary interval in the x direction.
  • the plurality of attachment holes 11 have a shape to which the microphone substrate 31 can be attached, and are formed at equal intervals in the x direction.
  • the N microphone substrates 31 are respectively attached to the N attachment holes 11 of one first support 10 so that the microphones mc are arranged at a constant interval d in the x direction.
  • the microphone substrate 31 can be attached to and detached from the first support 10, and the interval d in the x direction of the microphone mc can be arbitrarily changed.
  • the attachment holes 11 are formed in the x direction at intervals of, for example, about 3 mm, and the interval d in the x direction can be changed from, for example, from about 3 mm to about 20 mm.
  • the first support 10 has a plate-like shape whose length in the z direction is shorter than the length in the y direction perpendicular to the measurement surface. That is, the first support 10 extends perpendicular to the measurement surface.
  • the microphone substrate 31 is attached in parallel to a surface perpendicular to the measurement surface of the first support 10. Thereby, the mounting surface of the microphone mc becomes perpendicular to the measurement surface.
  • the microphone substrate 31 is attached to the first support 10 so that the microphone mc is located on the side close to the object to be measured in the y direction, that is, on the side close to the sound source surface 2a.
  • the microphone mc is disposed so as to protrude from the end surface of the first support 10 on the measured object side (the sound source surface 2a side) toward the measured object side (the sound source surface 2a side) in the y direction.
  • the first support 10 and the second support 20 are arranged on the opposite side of the measurement surface from the sound source surface 2a so as not to block the sound to be measured from the sound source.
  • the cable 41 extends to the control substrate 40 from the far side from the object to be measured (the sound source surface 2a) in the microphone substrate 31 in the y direction.
  • FIG. 4 is a diagram showing a configuration of the second support 20 in the present embodiment.
  • the second support 20 includes a plurality of mounting grooves (concave portions) 21 into which the first support 10 can be inserted in the z direction at arbitrary intervals.
  • the plurality of mounting grooves 21 have a shape into which the first support body 10 can be inserted, and are formed at equal intervals in the z direction.
  • the M first supports 10 are fixed by inserting the end portions into the mounting grooves 21 of the second support 20 so as to be arranged at a constant interval d in the z direction.
  • the 1st support body 10 can be attached or detached with respect to the 2nd support body 20, and the space
  • the mounting grooves 21 are formed in the z direction at intervals of about 3 mm, for example, and the interval d in the z direction can be changed between about 3 mm and about 20 mm, for example.
  • FIG. 5 is a diagram illustrating an example of connection between the microphone mc and the control board 40.
  • the control board 40 can perform control related to recording of the plurality of microphones mc.
  • One end of a plurality of cables 41 is connected to the control board 40, and the other ends of the plurality of cables 41 are connected to the microphone mc.
  • the M ⁇ N microphones mc included in the microphone array 1 may be connected to one control board 40 and controlled by one microphone control unit, or may be connected to a different control board 40 for each predetermined number of microphones mc. Each may be controlled by a plurality of microphone control units.
  • N microphones mc supported by one first support 10 may be connected to one control board 40, and one microphone control unit may perform control related to recording of the N microphones mc. Good. In this case, you may make it further provide the control part which controls the M microphone control part respectively corresponding to the M 1st support bodies 10.
  • the microphone array 1 includes the plurality of microphones (MEMS microphones) mc and the plurality of microphone substrates 31 on which the plurality of microphones mc are mounted one by one, and the first support.
  • a ladder-like support member including the body 10 and the second support body 20 has a configuration in which the microphone substrate 31 is detachably supported.
  • the microphone array 1 is brought closer to the object to be measured compared to a configuration in which a plurality of microphones are supported by a lattice-shaped support member.
  • the sound can be prevented from being reflected by the support member.
  • adverse effects of the reflected sound from the microphone array 1 on the acoustic analysis result can be suppressed.
  • the first support 10 has a plurality of mounting holes 11 in which the microphone substrate 31 can be mounted at an arbitrary interval, and can support the plurality of microphone substrates 31 at an arbitrary constant interval in the x direction.
  • the second support 20 has a plurality of mounting grooves 21 into which the first support 10 can be inserted at an arbitrary interval, and the plurality of first supports 10 have an arbitrary constant interval in the z direction. Can be arranged in parallel. With such a configuration, the degree of freedom of arrangement of the microphones mc can be increased, and the positional relationship (interval d) between the microphones mc can be freely adjusted according to the size of the object to be measured. Therefore, it is not necessary to prepare a microphone array corresponding to each object to be measured, and the cost can be reduced accordingly. Further, the distance d can be easily adjusted with a relatively simple configuration.
  • a microphone array using a MEMS microphone has a configuration in which a plurality of MEMS microphones are surface-mounted on one substrate. Therefore, if any trouble occurs in one of the plurality of MEMS microphones, the entire board must be repaired and replaced.
  • each of the plurality of MEMS microphones is surface-mounted on the microphone substrate one by one. Therefore, when any trouble occurs in one of the plurality of MEMS microphones, It is only necessary to repair or replace the microphone substrate on which the defective MEMS microphone is mounted.
  • a method is known in which a plurality of MEMS microphones are mounted on a lattice-shaped substrate, and a microphone array is configured by the substrate itself.
  • the grid-like interval cannot be changed according to the size of the object to be measured, and it is necessary to manufacture a microphone array from the substrate for each object to be measured.
  • a plurality of MEMS microphones are mounted on independent microphone substrates, and the plurality of microphone substrates can be arranged at arbitrary intervals. Therefore, it is possible to deal with objects of various sizes with one microphone array.
  • the object to be measured is small, there is a case where it is desired to set the grating interval of the microphone to 1 cm or less, for example.
  • the microphone array is regarded as a wall and the sound is reflected, and the sound is measured between the object to be measured and the microphone array. Will echo.
  • the reflected sound is superimposed on the sound to be measured, which hinders accurate measurement. As a result, sound analysis using this microphone array becomes difficult.
  • the microphone substrate 31 on which the microphone mc is mounted is disposed perpendicular to the measurement surface. Therefore, even if the grating interval d of the microphone mc is narrow, the measurement surface of the microphone array 1 can be prevented from having a dense structure, and the generation of the reflected sound described above can be suppressed.
  • the microphone mc can be a non-directional microphone. Thereby, the sound collection by the microphone mc can be appropriately performed regardless of the posture of the microphone substrate 31.
  • the microphone mc can be a MEMS microphone. As described above, by using the MEMS microphone, a microphone array capable of realizing a small near-field acoustic holography for a small object to be analyzed can be obtained.
  • the first support 10 in a shape extending perpendicularly to the measurement surface, it is possible to suppress the first support 10 from becoming a wall and to suppress the generation of reflected sound. Furthermore, by attaching the microphone substrate 31 to a surface perpendicular to the measurement surface of the first support 10, the microphone substrate 31 can be easily and appropriately disposed perpendicular to the measurement surface. Further, the postures of the plurality of microphone substrates 31 can be easily aligned vertically.
  • the microphone mc is mounted on the microphone substrate 31 at a position close to the object to be measured. As a result, it is possible to appropriately collect sound by the microphone mc. Furthermore, at this time, by arranging the microphone mc so as to protrude from the end surface of the first support 10 on the measured object side toward the measured object side, it is possible to collect sound more appropriately. Further, since the cable 41 extends from the far side of the microphone substrate 31 to the object to be measured to the control board 40, the cable 41 does not interfere with sound collection.
  • the microphone array 1 can easily adjust the positional relationship between the microphones mc according to the size of the object to be measured, and appropriately measures the sound to be measured from the object to be measured. can do.
  • the object to be measured is small and the lattice distance of the microphone mc is narrow, a structure in which the sound to be measured from the object to be measured is not blocked can be obtained. Therefore, sound to be measured from various small objects to be measured can be accurately measured by the single microphone array 1.
  • FIG. 6 is a configuration example of an acoustic analysis system 1000 including the microphone array 1 in the present embodiment.
  • the acoustic analysis system 1000 includes the above-described microphone array 1, the acoustic analysis device 100, and the display device 200.
  • the acoustic analysis device 100 analyzes a signal input from each of the plurality of microphones mc, and detects a physical quantity that represents a feature of the sound.
  • the microphone array 1 is disposed in the vicinity of the device under test 2 so that the measurement surface is parallel to the sound source surface 2a of the device under test 2.
  • the acoustic analysis apparatus 100 includes a signal processing unit 101, an analysis processing unit 102, and a storage unit 103.
  • the signal processing unit 101 performs predetermined signal processing on the signal from each microphone mc of the microphone array 1 to obtain a signal used for acoustic analysis.
  • the signal processing may include processing for synchronizing signals of M ⁇ N microphones mc included in the microphone array 1.
  • the analysis processing unit 102 analyzes the signal subjected to the signal processing by the signal processing unit 101 and detects a physical quantity representing the feature of the sound.
  • the physical quantity representing the characteristics of the sound includes a sound pressure distribution, a particle velocity distribution, and the like. Then, the analysis processing unit 102 generates an image corresponding to the physical quantity representing the feature of the sound, and performs display control for displaying the image on the display device 200.
  • the storage unit 103 stores the analysis result by the analysis processing unit 102 and the like.
  • the display device 200 includes a monitor such as a liquid crystal display, and displays the image that is the analysis result of the acoustic analysis device 100.
  • the acoustic analysis system 1000 includes the microphone array 1 for near-field acoustic holography, in which the lattice distance of the microphone mc is small and variable. Acoustic analysis is possible.
  • the acoustic analysis system 1000 including the M ⁇ N microphone array includes, for example, M microphone array modules that perform control related to recording of N microphones mc, and a control unit that controls the M microphone array modules.
  • M microphone array modules that perform control related to recording of N microphones mc
  • control unit that controls the M microphone array modules.
  • the microphone array module receives the signals of the N microphones mc, and transmits the received signals of the N microphones mc to the control unit.
  • the control unit receives the signal of the microphone mc from each of the M microphone array modules and processes it as a signal for use in acoustic analysis.
  • the control unit may perform processing for aligning the phases of the signals of the microphones mc received from the respective microphone array modules.
  • the N microphones mc included in one microphone array module are electrically synchronized.
  • the N microphones mc included in one microphone array module may be N microphones mc supported by one first support 10.
  • the number of microphones mc constituting the microphone array 1 can be easily increased by adding a microphone array module. Therefore, the size of the microphone array 1 can be increased in accordance with the size of the object to be measured, and the spatial resolution can be improved.
  • the microphone substrate 31 is disposed perpendicular to the measurement surface on which the plurality of microphones mc are disposed.
  • the microphone substrate 31 is disposed perpendicularly or substantially perpendicular to the measurement surface. It only has to be. That is, the microphone substrate 31 may be disposed to be inclined with respect to the measurement surface. Also in this case, the effect of suppressing the influence of the reflected sound by the microphone array 1 can be obtained. Further, a plurality of M ⁇ N microphone arrays 1 in the above embodiment may be connected to form a larger microphone array.
  • SYMBOLS 1 Microphone array, 2 ... Measured object (sound source), 2a ... Sound source surface, 10 ... First support body, 11 ... Mounting hole, 20 ... Second support body, 21 ... Mounting groove (concave part), 31 ... Microphone board, 40 ... control board, 41 ... cable, 100 ... acoustic analysis device, 200 ... display device, 1000 ... acoustic analysis system, mc ... microphone

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Multimedia (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Circuit For Audible Band Transducer (AREA)
  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)

Abstract

A microphone array 1 is provided with: a plurality of MEMS microphones; a plurality of microphone substrates on which the respective MEMS microphones are mounted; and a support member which attachably/detachably supports the plurality of microphone substrates. The microphone substrates can be disposed so as to be perpendicular or substantially perpendicular to measurement surfaces on which the plurality of MEMS microphones are disposed.

Description

マイクロホンアレイおよび音響解析システムMicrophone array and acoustic analysis system
　本発明は、マイクロホンアレイおよび音響解析システムに関する。 The present invention relates to a microphone array and an acoustic analysis system.
　近年、製品の低騒音化の要求の高まりから、音場の空間的分布を測定し解析することが要求されている。
　特許文献１には、複数のマイクロホンを格子状に配列し、複数の位置で音を検知するマイクロホンアレイを用いた音圧分布解析システムが開示されている。この音圧分布解析システムは、多チャンネル信号の増幅が可能なアンプを備え、当該アンプがマイクロホンのそれぞれの音信号を増幅し、解析端末に対して出力する。解析端末は、アンプから入力された音信号をＡ／Ｄ変換し、時間波形として記録する。 In recent years, due to the increasing demand for noise reduction of products, it is required to measure and analyze the spatial distribution of the sound field.
Patent Document 1 discloses a sound pressure distribution analysis system using a microphone array in which a plurality of microphones are arranged in a lattice pattern and sounds are detected at a plurality of positions. This sound pressure distribution analysis system includes an amplifier capable of amplifying a multi-channel signal, and the amplifier amplifies each sound signal of the microphone and outputs it to the analysis terminal. The analysis terminal A / D converts the sound signal input from the amplifier and records it as a time waveform.
日本国公開公報特開２００５－９１２７２号公報Japanese Laid-Open Patent Publication No. 2005-91272
　しかしながら、上記従来のマイクロホンアレイにおいては、コンデンサーマイク、あるいはダイナミックマイクを用いており、マイクロホンを例えば１ｃｍ以下の間隔で配置するとマイクロホンアレイの測定面が密な構造となり、マイクロホンアレイからの反射音の影響により音響ホログラフィの解析を行うことが困難となる。
　そこで、基板上に表面実装可能な小型のＭＥＭＳ（Micro-Electrical-Mechanical Systems）マイクロホンを用いたマイクロホンアレイが知られている。このようなＭＥＭＳマイクロホンアレイとして、格子状の基板に複数のＭＥＭＳマイクロホンを表面実装し、基板そのものでマイクロホンアレイを構成する方法が知られている。
　ところが、ＭＥＭＳマイクロホンアレイでは、一般に複数のＭＥＭＳマイクロホンが１つの基板に表面実装されるため、複数のＭＥＭＳマイクロホンのうちの１つに何らかの不具合が生じた場合、基板ごと修理、交換する必要があり、コストが嵩む。
　そこで、本発明は、複数のＭＥＭＳマイクロホンを個々の単位で容易に交換することができるマイクロホンアレイおよび音響解析システムを提供することを目的とする。 However, in the above conventional microphone array, a condenser microphone or a dynamic microphone is used. If the microphones are arranged at intervals of 1 cm or less, for example, the measurement surface of the microphone array becomes a dense structure, and the influence of reflected sound from the microphone array This makes it difficult to analyze acoustic holography.
Therefore, a microphone array using a small MEMS (Micro-Electrical-Mechanical Systems) microphone that can be surface-mounted on a substrate is known. As such a MEMS microphone array, a method is known in which a plurality of MEMS microphones are surface-mounted on a lattice-shaped substrate, and the microphone array is configured by the substrate itself.
However, in a MEMS microphone array, since a plurality of MEMS microphones are generally surface-mounted on one substrate, if any malfunction occurs in one of the plurality of MEMS microphones, it is necessary to repair and replace the entire substrate. Cost increases.
Accordingly, an object of the present invention is to provide a microphone array and an acoustic analysis system that can easily exchange a plurality of MEMS microphones in individual units.
　上記課題を解決するために、本発明の一つの態様のマイクロホンアレイは、複数のＭＥＭＳマイクロホンと、前記複数のＭＥＭＳマイクロホンがそれぞれ１つずつ実装された複数のマイク基板と、前記複数のマイク基板の各々を着脱可能に支持する支持部材と、を備える。 In order to solve the above problems, a microphone array according to an aspect of the present invention includes a plurality of MEMS microphones, a plurality of microphone boards each having the plurality of MEMS microphones mounted thereon, and a plurality of microphone boards. And a support member that detachably supports each of them.
　また、本発明の一つの態様の音響解析システムは、前記複数のＭＥＭＳマイクロホンの各々から入力された信号を解析し、音の特徴を表す物理量を検出する音響解析装置を備える。 In addition, an acoustic analysis system according to one aspect of the present invention includes an acoustic analysis device that analyzes a signal input from each of the plurality of MEMS microphones and detects a physical quantity representing a feature of sound.
　本発明の一つの態様によれば、複数のＭＥＭＳマイクロホンがそれぞれ独立したマイク基板に実装されているため、複数のＭＥＭＳマイクロホンを個々の単位で容易に交換することができる。 According to one aspect of the present invention, since a plurality of MEMS microphones are mounted on independent microphone substrates, the plurality of MEMS microphones can be easily replaced in individual units.
図１は、本実施形態におけるマイクロホンアレイの全体図である。FIG. 1 is an overall view of a microphone array in the present embodiment. 図２は、マイクロホンの構成を示す図である。FIG. 2 is a diagram illustrating a configuration of the microphone. 図３は、第一の支持体の構成を示す図である。FIG. 3 is a diagram showing the configuration of the first support. 図４は、第二の支持体の構成を示す図である。FIG. 4 is a diagram showing the configuration of the second support. 図５は、マイクロホンと制御基板との接続例を示す図である。FIG. 5 is a diagram illustrating an example of connection between the microphone and the control board. 図６は、音響解析システムの一例を示す図である。FIG. 6 is a diagram illustrating an example of an acoustic analysis system.
  以下、図面を用いて本発明の実施の形態について説明する。
　なお、本発明の範囲は、以下の実施の形態に限定されるものではなく、本発明の技術的思想の範囲内で任意に変更可能である。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The scope of the present invention is not limited to the following embodiment, and can be arbitrarily changed within the scope of the technical idea of the present invention.
　図１は、本実施形態におけるマイクロホンアレイ１の全体図である。
　本実施形態におけるマイクロホンアレイ１は、近接場音響ホログラフィ法を使用して被測定物（音源）からの被測定音を解析する音響解析システムに用いることができる。近接場音響ホログラフィ法では、音源面に近接し且つ平行な測定面の音圧分布を測定する必要があり、複数のマイクロホンを格子状に配置したマイクロホンアレイが用いられる。 FIG. 1 is an overall view of a microphone array 1 in the present embodiment.
The microphone array 1 in the present embodiment can be used in an acoustic analysis system that analyzes a sound to be measured from an object to be measured (sound source) using a near-field acoustic holography method. In the near-field acoustic holography method, it is necessary to measure the sound pressure distribution on a measurement surface that is close to and parallel to the sound source surface, and a microphone array in which a plurality of microphones are arranged in a lattice shape is used.
　図１に示すように、マイクロホンアレイ１は、複数の第一の支持体１０と、複数の第二の支持体２０と、複数のマイクロホンｍｃと、を備える。複数のマイクロホンｍｃの各々は、ＭＥＭＳ（Micro-Electrical-Mechanical Systems）マイクロホンである。
　第一の支持体１０は、それぞれ第一の方向（ｘ方向）を長手方向とする部材である。本実施形態では、マイクロホンアレイ１は、Ｍ本（図１では８本）の第一の支持体１０を備える。
　第二の支持体２０は、それぞれ第一の方向（ｘ方向）に対して直交する第二の方向（ｚ方向）を長手方向とする部材である。本実施形態では、マイクロホンアレイ１は、２本の第二の支持体２０を備える。２本の第二の支持体２０は、Ｍ本の第一の支持体１０の両端をそれぞれ着脱可能に支持する。 As shown in FIG. 1, the microphone array 1 includes a plurality of first supports 10, a plurality of second supports 20, and a plurality of microphones mc. Each of the plurality of microphones mc is a MEMS (Micro-Electrical-Mechanical Systems) microphone.
The 1st support body 10 is a member which makes a 1st direction (x direction) a longitudinal direction, respectively. In the present embodiment, the microphone array 1 includes M (eight in FIG. 1) first supports 10.
The 2nd support body 20 is a member which makes the 2nd direction (z direction) orthogonal to a 1st direction (x direction) a longitudinal direction, respectively. In the present embodiment, the microphone array 1 includes two second supports 20. The two second supports 20 detachably support both ends of the M first supports 10.
　第一の支持体１０は、それぞれＮ個（図１では８個）のマイクロホンｍｃをｘ方向において一定間隔ｄに配置した状態で支持している。また、第一の支持体１０は、ｚ方向において一定間隔ｄで並列配列されている。各第一の支持体１０において、マイクロホンｍｃのｘ方向における位置は同一である。つまり、Ｍ本の第一の支持体１０によって、Ｍ×Ｎ個のマイクロホンｍｃがｘｚ方向に格子状に配置されている。 The first support 10 supports N (eight in FIG. 1) microphones mc arranged at a constant interval d in the x direction. Moreover, the 1st support body 10 is arranged in parallel by the fixed space | interval d in the z direction. In each first support 10, the position of the microphone mc in the x direction is the same. That is, M × N microphones mc are arranged in a lattice pattern in the xz direction by M first supports 10.
　図１において、ｘｚ平面は、マイクロホンアレイ１のマイクロホンｍｃが格子状に配置された測定面に平行な面であり、被測定物の音源面に平行な面となる。マイクロホンアレイ１は、測定面を被測定物の音源面に対してｙ方向に所定距離離間した状態で配置される。例えば、マイクロホンアレイ１は、測定面と音源面とのｙ方向における距離が１ｃｍ以内となるよう配置される。 In FIG. 1, the xz plane is a plane parallel to the measurement surface on which the microphones mc of the microphone array 1 are arranged in a grid, and is a plane parallel to the sound source surface of the object to be measured. The microphone array 1 is arranged in a state where the measurement surface is separated from the sound source surface of the object to be measured by a predetermined distance in the y direction. For example, the microphone array 1 is arranged such that the distance between the measurement surface and the sound source surface in the y direction is within 1 cm.
　第一の支持体１０と第二の支持体２０とにより、複数のマイクロホンｍｃを支持する支持部材が構成されている。なお、当該支持部材は、図１に示す構成に限定されるものではない。支持部材は、複数の第一の支持体１０と、少なくとも１つの第二の支持体２０とを備えればよい。例えば、第二の支持体２０は、第一の支持体１０の一端のみを支持してもよいし、第一の支持体１０の端部以外の位置を支持してもよい。 The first support member 10 and the second support member 20 constitute a support member that supports the plurality of microphones mc. In addition, the said supporting member is not limited to the structure shown in FIG. The support member may include a plurality of first supports 10 and at least one second support 20. For example, the second support 20 may support only one end of the first support 10 or may support a position other than the end of the first support 10.
　マイクロホンｍｃは、全方向から収音可能な無指向性のＭＥＭＳマイクロホンである。
　図２に示すように、マイクロホンｍｃは、ＭＥＭＳ技術を用いた音響トランスデューサ（ＭＥＭＳチップ）とアンプとを内蔵し、小型基板であるマイク基板３１の表面に実装されている。マイクロホンｍｃは、音響トランスデューサによって音（音圧）を電気信号に変換し、変換した電気信号をアンプによって増幅して出力する。なお、マイクロホンｍｃがデジタルマイクロホンである場合、マイクロホンｍｃは、さらにＡ／Ｄコンバータを内蔵し、アンプによって増幅されたアナログ信号をデジタル信号に変換して出力することができる。 The microphone mc is an omnidirectional MEMS microphone capable of collecting sound from all directions.
As shown in FIG. 2, the microphone mc incorporates an acoustic transducer (MEMS chip) using an MEMS technology and an amplifier, and is mounted on the surface of a microphone substrate 31 which is a small substrate. The microphone mc converts sound (sound pressure) into an electrical signal using an acoustic transducer, amplifies the converted electrical signal using an amplifier, and outputs the amplified signal. When the microphone mc is a digital microphone, the microphone mc further includes an A / D converter, and can convert an analog signal amplified by an amplifier into a digital signal and output the digital signal.
　本実施形態では、複数のマイクロホンｍｃは、それぞれ独立したマイク基板３１に１つずつ実装されており、上記支持部材は、複数のマイク基板３１の各々を着脱可能に支持する。具体的には、Ｍ本の第一の支持体１０は、それぞれＮ個のマイク基板３１をｘ方向において一定間隔ｄで支持している。各マイク基板３１は、当該マイク基板３１に形成された取付穴３１ａを介して第一の支持体１０に着脱可能に取り付けられる。
　また、マイク基板３１には、コネクタ部３２が設けられている。コネクタ部３２には、マイクロホンｍｃと当該マイクロホンｍｃを制御する制御基板４０（図５参照）とを接続するためのケーブル４１のコネクタ部４１ａが接続される。つまり、マイクロホンｍｃは、ケーブル４１を介して制御基板４０に接続される。 In the present embodiment, each of the plurality of microphones mc is mounted on each independent microphone substrate 31, and the support member detachably supports each of the plurality of microphone substrates 31. Specifically, the M first supports 10 each support N microphone substrates 31 at a constant interval d in the x direction. Each microphone substrate 31 is detachably attached to the first support 10 through an attachment hole 31 a formed in the microphone substrate 31.
The microphone board 31 is provided with a connector portion 32. The connector part 32 is connected to a connector part 41a of a cable 41 for connecting the microphone mc and a control board 40 (see FIG. 5) for controlling the microphone mc. That is, the microphone mc is connected to the control board 40 via the cable 41.
　図３は、本実施形態における第一の支持体１０の一部を示す構成図である。なお、この図３では、図２におけるケーブル４１およびコネクタ部４１ａをマイク基板３１から取り外した状態を示している。
　この図３に示すように、第一の支持体１０は、マイク基板３１をｘ方向に任意の間隔で取付可能な複数の取付穴１１を備える。複数の取付穴１１は、マイク基板３１を取付可能な形状を有し、ｘ方向に等間隔に形成されている。Ｎ個のマイク基板３１は、マイクロホンｍｃがｘ方向に一定間隔ｄで配置するように、１つの第一の支持体１０のＮ個の取付穴１１にそれぞれ取り付けられる。マイク基板３１は、第一の支持体１０に対して着脱可能であり、マイクロホンｍｃのｘ方向における間隔ｄは、任意に変更することが可能となっている。ここで、取付穴１１は、ｘ方向に例えば３ｍｍ程度の間隔で形成されており、ｘ方向における間隔dは、例えば３ｍｍ程度から２０ｍｍ程度までの間で変更可能である。 FIG. 3 is a configuration diagram showing a part of the first support 10 in the present embodiment. 3 shows a state where the cable 41 and the connector part 41a in FIG.
As shown in FIG. 3, the first support 10 includes a plurality of mounting holes 11 that can mount the microphone substrate 31 at an arbitrary interval in the x direction. The plurality of attachment holes 11 have a shape to which the microphone substrate 31 can be attached, and are formed at equal intervals in the x direction. The N microphone substrates 31 are respectively attached to the N attachment holes 11 of one first support 10 so that the microphones mc are arranged at a constant interval d in the x direction. The microphone substrate 31 can be attached to and detached from the first support 10, and the interval d in the x direction of the microphone mc can be arbitrarily changed. Here, the attachment holes 11 are formed in the x direction at intervals of, for example, about 3 mm, and the interval d in the x direction can be changed from, for example, from about 3 mm to about 20 mm.
　第一の支持体１０は、ｚ方向の長さが、測定面に対して直交するｙ方向の長さよりも短い板状の形状を有する。つまり、第一の支持体１０は、測定面に対して垂直に延びる。また、マイク基板３１は、第一の支持体１０における測定面に対して垂直な面に平行に取り付けられる。これにより、マイクロホンｍｃの実装面は、測定面に対して垂直となる。
　また、マイク基板３１は、マイクロホンｍｃがｙ方向において被測定物に近い側、すなわち音源面２ａに近い側に位置するように第一の支持体１０に取り付けられている。より具体的には、マイクロホンｍｃは、ｙ方向において、第一の支持体１０の被測定物側（音源面２ａ側）の端面から、当該被測定物側（音源面２ａ側）に突出して配置されている。つまり、第一の支持体１０および第二の支持体２０は、音源からの被測定音を遮らないよう、測定面に対し音源面２ａとは反対側に配置されている。
　このマイク基板３１にケーブル４１が接続された状態では、ケーブル４１は、ｙ方向において、マイク基板３１における被測定物（音源面２ａ）から遠い側から制御基板４０へ延びる。 The first support 10 has a plate-like shape whose length in the z direction is shorter than the length in the y direction perpendicular to the measurement surface. That is, the first support 10 extends perpendicular to the measurement surface. In addition, the microphone substrate 31 is attached in parallel to a surface perpendicular to the measurement surface of the first support 10. Thereby, the mounting surface of the microphone mc becomes perpendicular to the measurement surface.
The microphone substrate 31 is attached to the first support 10 so that the microphone mc is located on the side close to the object to be measured in the y direction, that is, on the side close to the sound source surface 2a. More specifically, the microphone mc is disposed so as to protrude from the end surface of the first support 10 on the measured object side (the sound source surface 2a side) toward the measured object side (the sound source surface 2a side) in the y direction. Has been. That is, the first support 10 and the second support 20 are arranged on the opposite side of the measurement surface from the sound source surface 2a so as not to block the sound to be measured from the sound source.
In a state where the cable 41 is connected to the microphone substrate 31, the cable 41 extends to the control substrate 40 from the far side from the object to be measured (the sound source surface 2a) in the microphone substrate 31 in the y direction.
　図４は、本実施形態における第二の支持体２０の構成を示す図である。
　この図４に示すように、第二の支持体２０は、第一の支持体１０をｚ方向に任意の間隔で挿入可能な複数の取付溝（凹部）２１を備える。複数の取付溝２１は、第一の支持体１０を挿入可能な形状を有し、ｚ方向に等間隔に形成されている。Ｍ個の第一の支持体１０は、ｚ方向に一定間隔ｄで配置するように、端部が第二の支持体２０の取付溝２１に挿入されることで、固定される。第一の支持体１０は、第二の支持体２０に対して着脱可能であり、第一の支持体１０のｚ方向における間隔ｄは、任意に変更することが可能となっている。ここで、取付溝２１は、ｚ方向に例えば３ｍｍ程度の間隔で形成されており、ｚ方向における間隔dは、例えば３ｍｍ程度から２０ｍｍ程度までの間で変更可能である。 FIG. 4 is a diagram showing a configuration of the second support 20 in the present embodiment.
As shown in FIG. 4, the second support 20 includes a plurality of mounting grooves (concave portions) 21 into which the first support 10 can be inserted in the z direction at arbitrary intervals. The plurality of mounting grooves 21 have a shape into which the first support body 10 can be inserted, and are formed at equal intervals in the z direction. The M first supports 10 are fixed by inserting the end portions into the mounting grooves 21 of the second support 20 so as to be arranged at a constant interval d in the z direction. The 1st support body 10 can be attached or detached with respect to the 2nd support body 20, and the space | interval d in the z direction of the 1st support body 10 can be changed arbitrarily. Here, the mounting grooves 21 are formed in the z direction at intervals of about 3 mm, for example, and the interval d in the z direction can be changed between about 3 mm and about 20 mm, for example.
　図５は、マイクロホンｍｃと制御基板４０との接続例を示す図である。
　制御基板４０は、複数のマイクロホンｍｃの録音に関する制御を行うことができる。制御基板４０には、複数のケーブル４１の一端が接続されており、これら複数のケーブル４１の他端がそれぞれマイクロホンｍｃに接続される。
　マイクロホンアレイ１が有するＭ×Ｎ個のマイクロホンｍｃは、１つの制御基板４０に接続され、１つのマイク制御部により制御されてもよいし、所定数のマイクロホンｍｃごとに異なる制御基板４０に接続され、複数のマイク制御部によってそれぞれ制御されてもよい。例えば、１つの第一の支持体１０が支持するＮ個のマイクロホンｍｃが１つの制御基板４０に接続され、１つのマイク制御部が当該Ｎ個のマイクロホンｍｃの録音に関する制御を行うようにしてもよい。この場合、Ｍ個の第一の支持体１０にそれぞれ対応するＭ個のマイク制御部を制御する制御部をさらに備えるようにしてもよい。 FIG. 5 is a diagram illustrating an example of connection between the microphone mc and the control board 40.
The control board 40 can perform control related to recording of the plurality of microphones mc. One end of a plurality of cables 41 is connected to the control board 40, and the other ends of the plurality of cables 41 are connected to the microphone mc.
The M × N microphones mc included in the microphone array 1 may be connected to one control board 40 and controlled by one microphone control unit, or may be connected to a different control board 40 for each predetermined number of microphones mc. Each may be controlled by a plurality of microphone control units. For example, N microphones mc supported by one first support 10 may be connected to one control board 40, and one microphone control unit may perform control related to recording of the N microphones mc. Good. In this case, you may make it further provide the control part which controls the M microphone control part respectively corresponding to the M 1st support bodies 10.
　以上のように、本実施形態におけるマイクロホンアレイ１は、複数のマイクロホン（ＭＥＭＳマイクロホン）ｍｃと、複数のマイクロホンｍｃがそれぞれ１つずつ実装された複数のマイク基板３１と、を備え、第一の支持体１０と第二の支持体２０とを備える梯子状の支持部材がマイク基板３１を着脱可能に支持する構成を有する。
　このように、複数のマイクロホンｍｃがそれぞれ独立したマイク基板３１に実装されているため、複数のマイクロホンｍｃを個々の単位で容易に交換することができる。また、複数のマイクロホンｍｃは、梯子状の支持部材により支持されているため、例えば格子状の支持部材に複数のマイクロホンが支持された構成と比較して、マイクロホンアレイ１を被測定物に近接させて配置した場合に、支持部材により音声が反射してしまうことを抑制することができる。その結果、マイクロホンアレイ１からの反射音が音響解析結果へ及ぼす悪影響を抑制することができる。 As described above, the microphone array 1 according to the present embodiment includes the plurality of microphones (MEMS microphones) mc and the plurality of microphone substrates 31 on which the plurality of microphones mc are mounted one by one, and the first support. A ladder-like support member including the body 10 and the second support body 20 has a configuration in which the microphone substrate 31 is detachably supported.
As described above, since the plurality of microphones mc are mounted on the independent microphone substrates 31, the plurality of microphones mc can be easily replaced in individual units. Further, since the plurality of microphones mc are supported by a ladder-shaped support member, for example, the microphone array 1 is brought closer to the object to be measured compared to a configuration in which a plurality of microphones are supported by a lattice-shaped support member. The sound can be prevented from being reflected by the support member. As a result, adverse effects of the reflected sound from the microphone array 1 on the acoustic analysis result can be suppressed.
　さらに、第一の支持体１０は、マイク基板３１を任意の間隔で取付可能な複数の取付穴１１を有し、複数のマイク基板３１をｘ方向において任意の一定間隔で支持可能である。また、第二の支持体２０は、第一の支持体１０を任意の間隔で挿入可能な複数の取付溝２１を有し、複数の第一の支持体１０は、ｚ方向において任意の一定間隔で並列配置可能である。
　このような構成により、マイクロホンｍｃの配置の自由度を高めることができ、被測定物のサイズに応じてマイクロホンｍｃ同士の位置関係（間隔ｄ）を自由に調整することが可能となる。したがって、被測定物ごとに対応するマイクロホンアレイを用意する必要がなく、その分のコストを削減することができる。また、比較的簡易な構成で、容易に間隔ｄを調整することができる。 Furthermore, the first support 10 has a plurality of mounting holes 11 in which the microphone substrate 31 can be mounted at an arbitrary interval, and can support the plurality of microphone substrates 31 at an arbitrary constant interval in the x direction. The second support 20 has a plurality of mounting grooves 21 into which the first support 10 can be inserted at an arbitrary interval, and the plurality of first supports 10 have an arbitrary constant interval in the z direction. Can be arranged in parallel.
With such a configuration, the degree of freedom of arrangement of the microphones mc can be increased, and the positional relationship (interval d) between the microphones mc can be freely adjusted according to the size of the object to be measured. Therefore, it is not necessary to prepare a microphone array corresponding to each object to be measured, and the cost can be reduced accordingly. Further, the distance d can be easily adjusted with a relatively simple configuration.
　一般に、ＭＥＭＳマイクロホンを用いたマイクロホンアレイは、複数のＭＥＭＳマイクロホンを１つの基板に表面実装する構成を有する。そのため、複数のＭＥＭＳマイクロホンのうちの１つに何らかの不具合が生じた場合、基板ごと修理、交換しなければならない。これに対して、本実施形態では、上述したように複数のＭＥＭＳマイクロホンをそれぞれ１つずつマイク基板に表面実装するので、複数のＭＥＭＳマイクロホンのうちの１つに何らかの不具合が生じた場合には、不具合が生じたＭＥＭＳマイクロホンが実装されたマイク基板のみを修理、交換すればよい。
　また、従来、格子状の基板に複数のＭＥＭＳマイクロホンを実装し、基板そのものでマイクロホンアレイを構成する方法が知られている。しかしながら、この場合、被測定物の大きさに応じて格子状の間隔を変更することができず、被測定物ごとにマイクロホンアレイを基板から製作する必要がある。これに対して、本実施形態では、上述したように複数のＭＥＭＳマイクロホンをそれぞれ独立したマイク基板に実装し、これら複数のマイク基板を任意の間隔で配置可能とする。したがって、１つのマイクロホンアレイで様々な大きさの被測定物に対応することができる。 In general, a microphone array using a MEMS microphone has a configuration in which a plurality of MEMS microphones are surface-mounted on one substrate. Therefore, if any trouble occurs in one of the plurality of MEMS microphones, the entire board must be repaired and replaced. On the other hand, in the present embodiment, as described above, each of the plurality of MEMS microphones is surface-mounted on the microphone substrate one by one. Therefore, when any trouble occurs in one of the plurality of MEMS microphones, It is only necessary to repair or replace the microphone substrate on which the defective MEMS microphone is mounted.
Conventionally, a method is known in which a plurality of MEMS microphones are mounted on a lattice-shaped substrate, and a microphone array is configured by the substrate itself. However, in this case, the grid-like interval cannot be changed according to the size of the object to be measured, and it is necessary to manufacture a microphone array from the substrate for each object to be measured. In contrast, in the present embodiment, as described above, a plurality of MEMS microphones are mounted on independent microphone substrates, and the plurality of microphone substrates can be arranged at arbitrary intervals. Therefore, it is possible to deal with objects of various sizes with one microphone array.
　ところで、被測定物が小さい場合、マイクロホンの格子間隔を、例えば１ｃｍ以下にしたいといった場合がある。このような小型マイクロホンアレイを構成した場合、マイクロホンアレイの測定面が密な構造となっていると、マイクロホンアレイが壁とみなされて音が反射し、被測定物とマイクロホンアレイとの間で音が反響してしまう。定常状態での音を測定したい場合、反響した音が、測定したい音に重畳されるため、精確な測定の妨げとなる。その結果、このマイクロホンアレイを使用した音響の解析が困難となる。 By the way, when the object to be measured is small, there is a case where it is desired to set the grating interval of the microphone to 1 cm or less, for example. When such a small microphone array is configured, if the measurement surface of the microphone array has a dense structure, the microphone array is regarded as a wall and the sound is reflected, and the sound is measured between the object to be measured and the microphone array. Will echo. When it is desired to measure the sound in a steady state, the reflected sound is superimposed on the sound to be measured, which hinders accurate measurement. As a result, sound analysis using this microphone array becomes difficult.
　これに対して、本実施形態では、マイクロホンｍｃを実装したマイク基板３１を測定面に対して垂直に配置する。したがって、マイクロホンｍｃの格子間隔ｄが狭くても、マイクロホンアレイ１の測定面が密な構造になることを抑制し、上述した反射音の発生を抑制することができる。
　ここで、マイクロホンｍｃは、無指向性のマイクロホンとすることができる。これにより、マイク基板３１の姿勢にかかわらず、マイクロホンｍｃによる収音を適切に行うことができる。また、マイクロホンｍｃは、ＭＥＭＳマイクロホンとすることができる。このように、ＭＥＭＳマイクロホンを利用することで、小型の被解析対象向けの近接場音響ホログラフィを実現可能なマイクロホンアレイとすることができる。 On the other hand, in this embodiment, the microphone substrate 31 on which the microphone mc is mounted is disposed perpendicular to the measurement surface. Therefore, even if the grating interval d of the microphone mc is narrow, the measurement surface of the microphone array 1 can be prevented from having a dense structure, and the generation of the reflected sound described above can be suppressed.
Here, the microphone mc can be a non-directional microphone. Thereby, the sound collection by the microphone mc can be appropriately performed regardless of the posture of the microphone substrate 31. The microphone mc can be a MEMS microphone. As described above, by using the MEMS microphone, a microphone array capable of realizing a small near-field acoustic holography for a small object to be analyzed can be obtained.
　また、第一の支持体１０を、測定面に対して垂直に延びる形状とすることで、第一の支持体１０が壁となることを抑制し、反射音の発生を抑制することができる。さらに、マイク基板３１を、第一の支持体１０における測定面に対して垂直な面に取り付けることで、マイク基板３１を測定面に対して容易かつ適切に垂直に配置することができる。また、複数のマイク基板３１の姿勢を容易に垂直に揃えることができる。 Also, by forming the first support 10 in a shape extending perpendicularly to the measurement surface, it is possible to suppress the first support 10 from becoming a wall and to suppress the generation of reflected sound. Furthermore, by attaching the microphone substrate 31 to a surface perpendicular to the measurement surface of the first support 10, the microphone substrate 31 can be easily and appropriately disposed perpendicular to the measurement surface. Further, the postures of the plurality of microphone substrates 31 can be easily aligned vertically.
　また、マイクロホンｍｃは、マイク基板３１において、被測定物に近い位置に実装する。これにより、マイクロホンｍｃにより適切に音声を収音することができる。さらにこのとき、マイクロホンｍｃを、第一の支持体１０の被測定物側の端面から被測定物側に突出して配置することで、より適切に音声を収音することが可能となる。
　また、ケーブル４１は、マイク基板３１における被測定物から遠い側から制御基板４０へ延びる構成であるため、ケーブル４１が収音の妨げになることもない。 The microphone mc is mounted on the microphone substrate 31 at a position close to the object to be measured. As a result, it is possible to appropriately collect sound by the microphone mc. Furthermore, at this time, by arranging the microphone mc so as to protrude from the end surface of the first support 10 on the measured object side toward the measured object side, it is possible to collect sound more appropriately.
Further, since the cable 41 extends from the far side of the microphone substrate 31 to the object to be measured to the control board 40, the cable 41 does not interfere with sound collection.
　以上説明したように、本実施形態におけるマイクロホンアレイ１は、被測定物のサイズに応じてマイクロホンｍｃ同士の位置関係を容易に調整することができ、被測定物からの被測定音を適切に測定することができる。また、被測定物が小さく、マイクロホンｍｃの格子間隔が狭い場合であっても、被測定物からの被測定音を遮らない構成とすることができる。したがって、様々な小型の被測定物からの被測定音を、１つのマイクロホンアレイ１により精確に測定することができる。 As described above, the microphone array 1 according to the present embodiment can easily adjust the positional relationship between the microphones mc according to the size of the object to be measured, and appropriately measures the sound to be measured from the object to be measured. can do. In addition, even when the object to be measured is small and the lattice distance of the microphone mc is narrow, a structure in which the sound to be measured from the object to be measured is not blocked can be obtained. Therefore, sound to be measured from various small objects to be measured can be accurately measured by the single microphone array 1.
　図６は、本実施形態におけるマイクロホンアレイ１を備える音響解析システム１０００の構成例である。
　音響解析システム１０００は、上述したマイクロホンアレイ１と、音響解析装置１００と、表示装置２００と、を備える。音響解析装置１００は、複数のマイクロホンｍｃの各々から入力された信号を解析し、音の特徴を表す物理量を検出する。この音響解析システム１００において、マイクロホンアレイ１は、被測定物２の音源面２ａに対して測定面が平行となるように、被測定物２に近接して配置される。 FIG. 6 is a configuration example of an acoustic analysis system 1000 including the microphone array 1 in the present embodiment.
The acoustic analysis system 1000 includes the above-described microphone array 1, the acoustic analysis device 100, and the display device 200. The acoustic analysis device 100 analyzes a signal input from each of the plurality of microphones mc, and detects a physical quantity that represents a feature of the sound. In the acoustic analysis system 100, the microphone array 1 is disposed in the vicinity of the device under test 2 so that the measurement surface is parallel to the sound source surface 2a of the device under test 2.
　音響解析装置１００は、信号処理部１０１と、解析処理部１０２と、記憶部１０３と、を備える。信号処理部１０１は、マイクロホンアレイ１の各マイクロホンｍｃからの信号に対して所定の信号処理を行い、音響解析に用いる信号を得る。なお、当該信号処理は、マイクロホンアレイ１が備えるＭ×Ｎ個のマイクロホンｍｃの信号の同期をとる処理等を含んでいてもよい。 The acoustic analysis apparatus 100 includes a signal processing unit 101, an analysis processing unit 102, and a storage unit 103. The signal processing unit 101 performs predetermined signal processing on the signal from each microphone mc of the microphone array 1 to obtain a signal used for acoustic analysis. The signal processing may include processing for synchronizing signals of M × N microphones mc included in the microphone array 1.
　解析処理部１０２は、信号処理部１０１により信号処理された信号を解析し、音の特徴を表す物理量を検出する。ここで、音の特徴を表す物理量は、音圧分布や粒子速度分布等を含む。そして、解析処理部１０２は、音の特徴を表す物理量に対応する画像を生成し、当該画像を表示装置２００に表示させる表示制御を行う。
　記憶部１０３は、解析処理部１０２による解析結果等を記憶する。
　表示装置２００は、液晶ディスプレイ等のモニタを備え、音響解析装置１００の解析結果である上記画像を表示する。
　このように、本実施形態における音響解析システム１０００は、マイクロホンｍｃの格子間隔が小さく、且つ可変な近接場音響ホログラフィ用のマイクロホンアレイ１を備えるので、サイズの小さい被測定物について、精確な測定および音響解析が可能となる。 The analysis processing unit 102 analyzes the signal subjected to the signal processing by the signal processing unit 101 and detects a physical quantity representing the feature of the sound. Here, the physical quantity representing the characteristics of the sound includes a sound pressure distribution, a particle velocity distribution, and the like. Then, the analysis processing unit 102 generates an image corresponding to the physical quantity representing the feature of the sound, and performs display control for displaying the image on the display device 200.
The storage unit 103 stores the analysis result by the analysis processing unit 102 and the like.
The display device 200 includes a monitor such as a liquid crystal display, and displays the image that is the analysis result of the acoustic analysis device 100.
As described above, the acoustic analysis system 1000 according to the present embodiment includes the microphone array 1 for near-field acoustic holography, in which the lattice distance of the microphone mc is small and variable. Acoustic analysis is possible.
　なお、Ｍ×Ｎマイクロホンアレイを備える上記の音響解析システム１０００は、例えば、Ｎ個のマイクロホンｍｃの録音に関する制御を行うＭ個のマイクロホンアレイモジュールと、Ｍ個のマイクロホンアレイモジュールを制御する制御部と、を備える構成であってもよい。この場合、マイクロホンアレイモジュールは、Ｎ個のマイクロホンｍｃの信号を受信し、受信したＮ個のマイクロホンｍｃの信号を制御部に送信する。また、制御部は、Ｍ個のマイクロホンアレイモジュールからそれぞれマイクロホンｍｃの信号を受信し、音響解析に用いるための信号として処理する。 The acoustic analysis system 1000 including the M × N microphone array includes, for example, M microphone array modules that perform control related to recording of N microphones mc, and a control unit that controls the M microphone array modules. The structure provided with these may be sufficient. In this case, the microphone array module receives the signals of the N microphones mc, and transmits the received signals of the N microphones mc to the control unit. Further, the control unit receives the signal of the microphone mc from each of the M microphone array modules and processes it as a signal for use in acoustic analysis.
　このとき、制御部は、各マイクロホンアレイモジュールから受信したマイクロホンｍｃの信号の位相を揃える処理を行ってもよい。なお、１つのマイクロホンアレイモジュールが備えるＮ個のマイクロホンｍｃの同期は、電気的にとれているものとする。ここで、１つのマイクロホンアレイモジュールが備えるＮ個のマイクロホンｍｃは、１つの第一の支持体１０が支持するＮ個のマイクロホンｍｃとすることができる。
　この場合、マイクロホンアレイモジュールを追加することで、マイクロホンアレイ１を構成するマイクロホンｍｃの数を容易に増加することができる。したがって、被測定物のサイズに対応させてマイクロホンアレイ１のサイズを大きくしたり、空間分解能を良好にしたりすることができる。 At this time, the control unit may perform processing for aligning the phases of the signals of the microphones mc received from the respective microphone array modules. It is assumed that the N microphones mc included in one microphone array module are electrically synchronized. Here, the N microphones mc included in one microphone array module may be N microphones mc supported by one first support 10.
In this case, the number of microphones mc constituting the microphone array 1 can be easily increased by adding a microphone array module. Therefore, the size of the microphone array 1 can be increased in accordance with the size of the object to be measured, and the spatial resolution can be improved.
（変形例）
　上記実施形態においては、マイク基板３１を、複数のマイクロホンｍｃが配置された測定面に対して垂直に配置する場合について説明したが、マイク基板３１は測定面に対して垂直または略垂直に配置されていればよい。つまり、マイク基板３１は、測定面に対して傾斜して配置されていてもよい。この場合にも、マイクロホンアレイ１による反射音の影響を抑制する効果が得られる。
　また、上記実施形態におけるＭ×Ｎのマイクロホンアレイ１を複数連結し、さらに大きなマイクロホンアレイを構成してもよい。 (Modification)
In the above embodiment, the case where the microphone substrate 31 is disposed perpendicular to the measurement surface on which the plurality of microphones mc are disposed has been described. However, the microphone substrate 31 is disposed perpendicularly or substantially perpendicular to the measurement surface. It only has to be. That is, the microphone substrate 31 may be disposed to be inclined with respect to the measurement surface. Also in this case, the effect of suppressing the influence of the reflected sound by the microphone array 1 can be obtained.
Further, a plurality of M × N microphone arrays 1 in the above embodiment may be connected to form a larger microphone array.
　１…マイクロホンアレイ、２…被測定物（音源）、２ａ…音源面、１０…第一の支持体、１１…取付穴、２０…第二の支持体、２１…取付溝（凹部）、３１…マイク基板、４０…制御基板、４１…ケーブル、１００…音響解析装置、２００…表示装置、１０００…音響解析システム、ｍｃ…マイクロホン DESCRIPTION OF SYMBOLS 1 ... Microphone array, 2 ... Measured object (sound source), 2a ... Sound source surface, 10 ... First support body, 11 ... Mounting hole, 20 ... Second support body, 21 ... Mounting groove (concave part), 31 ... Microphone board, 40 ... control board, 41 ... cable, 100 ... acoustic analysis device, 200 ... display device, 1000 ... acoustic analysis system, mc ... microphone

Claims (12)

  1. 　複数のＭＥＭＳマイクロホンと、
    　前記複数のＭＥＭＳマイクロホンがそれぞれ１つずつ実装された複数のマイク基板と、
    　前記複数のマイク基板の各々を着脱可能に支持する支持部材と、を備えることを特徴とするマイクロホンアレイ。     A plurality of MEMS microphones;
    A plurality of microphone substrates each having one of the plurality of MEMS microphones mounted thereon;
    And a support member that removably supports each of the plurality of microphone substrates.
  2. 　前記マイク基板は、前記複数のＭＥＭＳマイクロホンが配置された測定面に対して垂直または略垂直に配置されていることを特徴とする請求項１に記載のマイクロホンアレイ。 The microphone array according to claim 1, wherein the microphone substrate is arranged perpendicularly or substantially perpendicular to a measurement surface on which the plurality of MEMS microphones are arranged.
  3. 　前記ＭＥＭＳマイクロホンの各々は、無指向性のＭＥＭＳマイクロホンであることを特徴とする請求項２に記載のマイクロホンアレイ。 The microphone array according to claim 2, wherein each of the MEMS microphones is an omnidirectional MEMS microphone.
  4. 　前記支持部材は、
    　　前記複数のマイク基板を着脱可能に支持する複数の第一の支持体と、
    　　前記複数の第一の支持体を着脱可能に支持する少なくとも１つの第二の支持体と、を備え、
    　前記第一の支持体は、
    　　前記マイク基板を第一の方向において任意の一定間隔で支持可能であり、
    　　前記第一の方向に直交する第二の方向において、任意の一定間隔で並列配置可能であることを特徴とする請求項１から３のいずれか１項に記載のマイクロホンアレイ。     The support member is
    A plurality of first supports that detachably support the plurality of microphone substrates;
    And at least one second support that removably supports the plurality of first supports.
    The first support is
    The microphone substrate can be supported at any regular interval in the first direction,
    The microphone array according to any one of claims 1 to 3, wherein the microphone array can be arranged in parallel at an arbitrary constant interval in a second direction orthogonal to the first direction.
  5. 　前記第一の支持体は、前記マイク基板を任意の間隔で取付可能な複数の取付穴を有することを特徴とする請求項４に記載のマイクロホンアレイ。 5. The microphone array according to claim 4, wherein the first support has a plurality of mounting holes to which the microphone substrate can be mounted at an arbitrary interval.
  6. 　前記第二の支持体は、前記第一の支持体を任意の間隔で挿入可能な複数の取付溝を有することを特徴とする請求項４または５に記載のマイクロホンアレイ。 The microphone array according to claim 4 or 5, wherein the second support has a plurality of mounting grooves into which the first support can be inserted at an arbitrary interval.
  7. 　前記第一の支持体は、前記第二の方向の長さが、前記複数のＭＥＭＳマイクロホンが配置された測定面に対して直交する方向の長さよりも短いことを特徴とする請求項４から６のいずれか１項に記載のマイクロホンアレイ。 The length of the first support in the second direction is shorter than a length in a direction orthogonal to a measurement surface on which the plurality of MEMS microphones are arranged. The microphone array according to any one of the above.
  8. 　前記マイク基板は、前記第一の支持体における前記測定面に対して垂直な面に取り付けられていることを特徴とする請求項７に記載のマイクロホンアレイ。 The microphone array according to claim 7, wherein the microphone substrate is attached to a surface perpendicular to the measurement surface of the first support.
  9. 　前記ＭＥＭＳマイクロホンは、前記第一の支持体の被測定物側の端面から前記被測定物側に突出して配置されていることを特徴とする請求項４から８のいずれか１項に記載のマイクロホンアレイ。 The microphone according to any one of claims 4 to 8, wherein the MEMS microphone is disposed so as to protrude from the end surface of the first support on the measured object side toward the measured object side. array.
  10. 　前記ＭＥＭＳマイクロホンは、前記マイク基板における被測定物に近い位置に実装されていることを特徴とする請求項１から９のいずれか１項に記載のマイクロホンアレイ。 The microphone array according to any one of claims 1 to 9, wherein the MEMS microphone is mounted at a position close to an object to be measured on the microphone substrate.
  11. 　前記ＭＥＭＳマイクロホンは、ケーブルを介して当該ＭＥＭＳマイクロホンを制御する
    制御基板に接続されており、
    　前記ケーブルは、前記マイク基板における前記被測定物から遠い側から前記制御基板へ延びていることを特徴とする請求項１０に記載のマイクロホンアレイ。     The MEMS microphone is connected to a control board that controls the MEMS microphone via a cable,
    The microphone array according to claim 10, wherein the cable extends to the control board from a side of the microphone board far from the object to be measured.
  12. 　請求項１から１１のいずれか１項に記載のマイクロホンアレイと、
    　前記複数のＭＥＭＳマイクロホンの各々から入力された信号を解析し、音の特徴を表す物理量を検出する音響解析装置と、を備えることを特徴とする音響解析システム。     The microphone array according to any one of claims 1 to 11,
    An acoustic analysis system comprising: an acoustic analysis device that analyzes a signal input from each of the plurality of MEMS microphones and detects a physical quantity representing a feature of sound.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004032314A (en) * 2002-06-25 2004-01-29 Fuji Xerox Co Ltd Microphone array
JP2007096839A (en) * 2005-09-29 2007-04-12 Yamaha Corp Rack for array system
JP2009278434A (en) * 2008-05-15 2009-11-26 Audio Technica Corp Microphone array
JP2012202958A (en) * 2011-03-28 2012-10-22 Ono Sokki Co Ltd Noise source identification system
JP2015012562A (en) * 2013-07-02 2015-01-19 パナソニック株式会社 Microphone array apparatus
JP2018011238A (en) * 2016-07-15 2018-01-18 パナソニックＩｐマネジメント株式会社 Microphone unit and noise reduction device using the same

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7365476B2 (en) * 2004-02-27 2008-04-29 The Boeing Company Methods and systems for supporting acoustical transducers

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004032314A (en) * 2002-06-25 2004-01-29 Fuji Xerox Co Ltd Microphone array
JP2007096839A (en) * 2005-09-29 2007-04-12 Yamaha Corp Rack for array system
JP2009278434A (en) * 2008-05-15 2009-11-26 Audio Technica Corp Microphone array
JP2012202958A (en) * 2011-03-28 2012-10-22 Ono Sokki Co Ltd Noise source identification system
JP2015012562A (en) * 2013-07-02 2015-01-19 パナソニック株式会社 Microphone array apparatus
JP2018011238A (en) * 2016-07-15 2018-01-18 パナソニックＩｐマネジメント株式会社 Microphone unit and noise reduction device using the same

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