CN107690121A - Multichannel microphone phase calibration system and its calibration method - Google Patents
Multichannel microphone phase calibration system and its calibration method Download PDFInfo
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- CN107690121A CN107690121A CN201711142402.5A CN201711142402A CN107690121A CN 107690121 A CN107690121 A CN 107690121A CN 201711142402 A CN201711142402 A CN 201711142402A CN 107690121 A CN107690121 A CN 107690121A
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- multichannel
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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
- H04R29/00—Monitoring arrangements; Testing arrangements
- H04R29/004—Monitoring arrangements; Testing arrangements for microphones
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- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
The invention discloses and provide a kind of multichannel microphone phase calibration system for rationally designing coupler and microphone, it can be realized the multichannel microphone phase calibration method that carries out using the multichannel microphone phase calibration system and refer to microphone using one, 3 microphones are calibrated simultaneously, and are calibrated phase error and met：±0.5°50Hz‑1000Hz；±1.0°1000Hz‑4000Hz；± 2.0 ° of 4000Hz 6000Hz requirement.The present invention is applied to microphone calibration field.
Description
Technical field
The present invention relates to a kind of multichannel microphone phase calibration system and its calibration method.
Background technology
At present, the phase calibrator of instrument manufacturer production can only realize one microphone of primary calibration, and calibration efficiency is low.Mesh
Before, due to the development and popularization of auditory localization technology, microphone matrix is promoted the use of, and in microphone matrix, microphone
Phase directly determines the accuracy of auditory localization, for this reason, it may be necessary to develop multichannel microphone phase calibration method and equipment.
And at present in phase alignment equipment, consider less for the structure type of the Installation And Calibration equipment end of microphone,
Numerical fluctuations scope is big when causing the microphone phase to calibrate；Calibration efficiency is low, can only once calibrate one；Or the reference needed
Microphone is more, it is necessary to 2 or more than 2；In longitudinally mounted mode, the spacing of microphone must be sufficiently large, otherwise can influence
Calibrate the frequency range of microphone.
The content of the invention
The technical problems to be solved by the invention are overcome the deficiencies in the prior art, there is provided one kind rationally design coupler and
The multichannel microphone phase calibration system of microphone, using the multichannel microphone phase calibration system come the multichannel that carries out
Microphone phase calibration method can be realized refers to microphone using one, while calibrates 3 microphones, and calibration phase error expires
Foot：±0.5°50Hz-1000Hz；±1.0°1000Hz-4000Hz；± 2.0 ° of 4000Hz-6000Hz requirement.
The technical solution adopted in the present invention is：Multichannel microphone phase calibration system in the present invention is put including power
Big device, data collecting instrument and the data analysis terminal being connected with the data collecting instrument, the multichannel microphone phase
Calibration system also includes the correcting mechanism being connected respectively with the power amplifier and the data collecting instrument, the calibration
Mechanism includes loudspeaker and sonic tube, and the loudspeaker is connected with the power amplifier, the head end of the sonic tube with
The output end of the loudspeaker is connected, and the end adaptation plug of the sonic tube is provided with sound-absorbing block, and the head end of the sound-absorbing block is in
Cone, in cylinder, the head end adaptation of the sound-absorbing block is placed in the interior of the end of the sonic tube for the end of the sound-absorbing block
Portion, the end of the sound-absorbing block are placed in the outside of the end of the sonic tube, and adaptation is provided with least one mould in the sonic tube
Block microphone mounting seat, each it is provided with several microphones in the modularization microphone mounting seat.
The vertex of a cone of head end in cone of the sound-absorbing block is in same horizontal line with the axis of the sonic tube.
The modularization microphone mounting seat is arranged between the head end of the sound-absorbing block and the head end of the sonic tube
Interval range in, be provided with four microphone mounting holes in each modularization microphone mounting seat, four are described transaudient
Outer wall of the device mounting hole along the modularization microphone mounting seat is circumferentially distributed.
Adaptation is provided with a microphone, the length direction of the microphone and the sound wave on the microphone mounting hole
The length direction of pipe is perpendicular, and the microphone is connected with the data collecting instrument.
Adaptation is provided with four modularization microphone mounting seats successively in the sonic tube, and four modularizations are transaudient
Device mounting seat is sequentially connected assembling.
The microphone mounting hole of the end face of the output end of the loudspeaker and the first modularization microphone mounting seat it
Between distance length scope be 90-140mm, the length range of each modularization microphone mounting seat is 30-45mm, every two
The distance between microphone mounting hole length range is 25-60mm in the individual adjacent modularization microphone mounting seat, described
The head end of sound-absorbing block is 300-450mm with the distance between the end of sonic tube length range, and the sound-absorbing block is in circle
The length range of the head end of taper is 165mm-170mm.
Using above-mentioned multichannel microphone phase calibration system come the multichannel microphone phase school realized in the present invention
Quasi- method, it comprises the following steps：
A. the power amplifier provides power amplification for the loudspeaker, and then the loudspeaker is defeated toward sonic tube inside
Go out sound pressure signal；
B. each microphone receives the sound pressure signal in step A and corresponding sound pressure signal is sent into the data
In Acquisition Instrument, wherein the sound pressure signal spread out of by the microphone in the first modularization microphone mounting seat is with reference to installation position
Put sound pressure signal pr0(t) sound pressure signal, spread out of by the microphone in remaining remaining modularization microphone mounting seat is installation
Position sound pressure signal pri(t)(i=1,2,3...)；
C. the reference installation site sound pressure signal p that data collecting instrument described in the data analysis terminal-pair is collectedr0(t) with
And installation site sound pressure signal pri(t) (i=1,2,3...) progress fast Fourier changes to obtain Pr0And P (f)i(f)(i=1,2,
3…)；
D. P is takenr0And P (f)i(f) phase of (i=1,2,3 ...), so as to obtain pahse_0 (f) and phase_i (f) (i=1,2,
3…)；
E. the data analysis terminal calculate microphone phase phase_if (f)=phase_0 (f)-phase_r0 (f) to be calibrated+
phase_i(f)+phase_0i(f)；
F. terminate to calibrate.
The step C, step D and step E foundation formula is：
Standard microphone sensitivity (1)
Microphone i sensitivity to be calibrated (2)
It can be obtained by formula (1) and (2)：
(3)
(4)
(5)
(6)
By formula (3), (4), (5) and (6), can obtain
(7)
By formula (3) and (7), can obtain
In formula, Zr is the installation site of standard microphone, and Zi is the installation site of calibration microphone, and r is reflectance factor, Ui and
Ur is the voltage signal values of acquisition system measurement.
The measuring accuracy of microphone mainly byIt is determined that the structure of calibrator (-ter) unit is exactly around raisingPrecision is set
Meter.
The beneficial effects of the invention are as follows：The installation site that the present invention passes through reasonable Arrangement microphone so that the present invention can
The precision of multiple microphones is calibrated simultaneously, and due to carrying out sound-absorbing in the sound-absorbing block of cone using head end, sound-absorbing effect is more
Add so that the phase of calibration is straight in low frequency region, and high-frequency energy reaches ± 2.0 ° of calibration accuracy.Microphone phase school simultaneously
The proper phase difference precision of quasi- instrument reaches：±0.5°50Hz~1000Hz；±1.0°1000Hz~4000Hz；±2.0°4000Hz~
6000Hz。
Brief description of the drawings
Fig. 1 is the Integral connection structure schematic diagram of the present invention；
Fig. 2 is the structural representation of alignment mechanism of the present invention,
Fig. 3 is influence state diagram of the head end of sound absorber to calibration；
Fig. 4 is influence of the spacing to calibration of microphone；
Fig. 5 is the length of head end and the graph of a relation of acoustic absorptivity of the sound-absorbing block in cone；
Fig. 6 is the calibration effect diagram on microphone.
Embodiment
As shown in Figure 1 and Figure 2, the multichannel microphone phase calibration system in the present invention includes power amplifier 1, data
Acquisition Instrument 2 and the data analysis terminal 3 being connected with the data collecting instrument 2, the multichannel microphone phase calibration system
System also includes the correcting mechanism 4 being connected respectively with the power amplifier 1 and the data collecting instrument 2, the adjusting machine
Structure 4 includes loudspeaker 41 and sonic tube 42, and the loudspeaker 41 is connected with the power amplifier 1, the sonic tube 42
Head end be connected with the output end of the loudspeaker 41, the end of the sonic tube 42 adaptation plug is provided with sound-absorbing block 43, described
Adaptation is provided with least one modularization microphone mounting seat 44 in sonic tube 42, in each modularization microphone mounting seat 44
It is provided with several microphones 441.The loudspeaker 41 is full frequency speaker.
The head end of the sound-absorbing block 43 is in cone, and the end of the sound-absorbing block 43 is in cylinder, the sound-absorbing block 43
Head end adaptation is placed in the inside of the end of the sonic tube 42, and the end of the sound-absorbing block 43 is placed in the end of the sonic tube 42
Outside.The vertex of a cone of head end in cone of the sound-absorbing block 43 is in same horizontal line with the axis of the sonic tube 42
On.The sound-absorbing block 43 is made up of strength sound-absorbing material.
The modularization microphone mounting seat 44 is arranged at the head end of the sound-absorbing block 43 and the head of the sonic tube 42
In interval range between end, four microphone mounting holes 441 are provided with each modularization microphone mounting seat 44, four
Outer wall of the individual microphone mounting hole 441 along the modularization microphone mounting seat 44 is circumferentially distributed.
Adaptation is provided with a microphone 442, the length direction of the microphone 442 on the microphone mounting hole 441
Perpendicular with the length direction of the sonic tube 42, the microphone 442 is connected with the data collecting instrument 2.
Adaptation is provided with several described modularization microphone mounting seats 44, several described moulds successively in the sonic tube 42
Block microphone mounting seat 44 is sequentially connected assembling.The end face of the output end of the loudspeaker 41 and the first modularization are transaudient
The distance between the microphone mounting hole 441 of device mounting seat 44 length range is 90-140mm, each modularization microphone
The length range of mounting seat 44 is 30-45mm, microphone installation in the adjacent modularization microphone mounting seat 44 of each two
The distance between hole 441 length range is 25-60mm, between the head end of the sound-absorbing block 43 and the end of the sonic tube 42
Distance length scope is 300-450mm, and the length range of the head end in cone of the sound-absorbing block 43 is 165mm-170mm.
In this specific embodiment, state in sonic tube 42 adaptation successively and be provided with four modularization microphone mounting seats
44, the microphone mounting hole 441 of the end face of the output end of the loudspeaker 41 and the first modularization microphone mounting seat 44
The distance between length be 140mm, the length of each modularization microphone mounting seat 44 is 45mm, the adjacent institute of each two
It is 60mm, the head of the sound-absorbing block 43 to state the distance between microphone mounting hole 441 length in modularization microphone mounting seat 44
The distance between end and the end of the sonic tube 42 length are 450mm.As shown in figure 5, when the sound-absorbing block 43 being in circular cone
When the length range of the head end of shape is 165mm-170mm, the acoustic absorptivity highest of the head end in cone of the sound-absorbing block 43,
In this specific embodiment, the length of the head end in cone of the sound-absorbing block 43 is 170mm.
Calibrated in the present invention using above-mentioned multichannel microphone phase calibration system come the multichannel microphone phase realized
Method, it comprises the following steps：
A. the power amplifier 1 is that the loudspeaker 41 provides power amplification, and then the loudspeaker 41 is toward the sonic tube
42 inside output sound pressure signals；
B. each microphone 442 receives the sound pressure signal in step A and is sent to corresponding sound pressure signal described
In data collecting instrument 2, wherein the sound pressure signal spread out of by the microphone 442 in the first modularization microphone mounting seat 44 is
With reference to installation site sound pressure signal pr0(t), spread out of by the microphone 442 in remaining remaining modularization microphone mounting seat 44
Sound pressure signal is installation site sound pressure signal pri(t)(i=1,2,3...)；
C. the reference installation site sound pressure signal p that the data analysis terminal 3 is collected to the data collecting instrument 2r0(t)
And installation site sound pressure signal pri(t) (i=1,2,3...) progress fast Fourier changes to obtain Pr0And P (f)i(f)(i=1,
2,3…)；
D. P is takenr0And P (f)i(f) phase of (i=1,2,3 ...), so as to obtain pahse_0 (f) and phase_i (f) (i=1,2,
3…)；
E. the data analysis terminal 3 calculates microphone phase phase_if (f) to be calibrated=phase_0 (f)-phase_r0 (f)
+phase_i(f)+phase_0i(f)；
F. terminate to calibrate.
The step C, step D and step E foundation formula is：
Standard microphone sensitivity (1)
Microphone i sensitivity to be calibrated (2)
It can be obtained by formula (1) and (2)：
(3)
(4)
(5)
(6)
By formula (3), (4), (5) and (6), can obtain
(7)
By formula (3) and (7), can obtain
In formula, Zr is the installation site of standard microphone, and Zi is the installation site of calibration microphone, and r is reflectance factor, Ui and
Ur is the voltage signal values of acquisition system measurement.
Above-mentioned formula is the deduction that is carried out on existing basic formula, and it is deduced according to being due toWithFor mark
Phase difference between the phase and Data Acquisition Channel of quasi- microphone, its value all very littles, particularlyLess than 0.05 °, can neglect
Slightly disregard, thus the measuring accuracy of microphone mainly byIt is determined that the structure of calibrator (-ter) unit is exactly around raisingPrecision is come
Design, as shown in Figure 3, Figure 4, wherein influenceing the head end that maximum factor is sound absorber, this hair for the measuring accuracy of microphone
The bright head end design by sound absorber coning, increases the area of sound absorber sound absorption, while cause sound wave and sound absorber body
Collision it is more smooth, reduce the reflection of sound wave, reduce influence of the head end to the precision of calibrator (-ter) unit of sound absorber as far as possible.
The present invention realizes refers to microphone using one, while calibrates 3 microphones, and calibrates phase error and meet：±0.5°
（50Hz-1000Hz）；±1.0°（1000Hz-4000Hz）；±2.0°（4000Hz-6000Hz）Requirement.
The design sketch of the calibration of microphone is as shown in fig. 6, wherein the signified curve of central stratum is in center in the present invention
Microphone effect line, the signified curve of secondary outer layer is the effect line of the microphone of adjacent central layer, the signified curve of outer layer
For the effect line of the microphone of most layer.
The present invention is applied to microphone calibration field.
Claims (8)
1. a kind of multichannel microphone phase calibration system, it includes power amplifier（1）, data collecting instrument（2）And with institute
State data collecting instrument（2）The data analysis terminal being connected（3）, it is characterised in that：The multichannel microphone phase calibration system
System also include respectively with the power amplifier（1）And the data collecting instrument（2）The correcting mechanism being connected（4）, it is described
Correcting mechanism（4）Including loudspeaker（41）And sonic tube（42）, the loudspeaker（41）With the power amplifier（1）It is connected
Connect, the sonic tube（42）Head end and the loudspeaker（41）Output end be connected, the sonic tube（42）End fit
Sound-absorbing block is provided with plug（43）, the sound-absorbing block（43）Head end in cone, the sound-absorbing block（43）End in cylinder,
The sound-absorbing block（43）Head end adaptation be placed in the sonic tube（42）End inside, the sound-absorbing block（43）End put
In the sonic tube（42）End outside, the sonic tube（42）Upper adaptation is provided with least one modularization microphone and installed
Seat（44）, each modularization microphone mounting seat（44）On be provided with several microphones（441）.
2. multichannel microphone phase calibration system according to claim 1, it is characterised in that：The sound-absorbing block（43）'s
The vertex of a cone and the sonic tube in the head end of cone（42）Axis be in same horizontal line.
3. multichannel microphone phase calibration system according to claim 2, it is characterised in that：The modularization microphone
Mounting seat（44）It is arranged at the sound-absorbing block（43）Head end and the sonic tube（42）Head end between interval range in,
Each modularization microphone mounting seat（44）On be provided with four microphone mounting holes（441）, four microphone peaces
Fill hole（441）Along the modularization microphone mounting seat（44）Outer wall be circumferentially distributed.
4. multichannel microphone phase calibration system according to claim 3, it is characterised in that：The microphone mounting hole
（441）Upper adaptation is provided with a microphone（442）, the microphone（442）Length direction and the sonic tube（42）'s
Length direction is perpendicular, the microphone（442）With the data collecting instrument（2）It is connected.
5. multichannel microphone phase calibration system according to claim 4, it is characterised in that：The sonic tube（42）On
Adaptation is provided with four modularization microphone mounting seats successively（44）, four modularization microphone mounting seats（44）Successively
It is linked and packed.
6. multichannel microphone phase calibration system according to claim 5, it is characterised in that：The loudspeaker（41）'s
The end face of output end and the first modularization microphone mounting seat（44）Microphone mounting hole（441）The distance between length
Scope is 90-140mm, each modularization microphone mounting seat（44）Length range be 30-45mm, each two is adjacent
The modularization microphone mounting seat（44）Upper microphone mounting hole（441）The distance between length range be 25-60mm, it is described
Sound-absorbing block（43）Head end and the sonic tube（42）The distance between end length range be 300-450mm, the sound-absorbing
Block（43）The length range of head end in cone be 165mm-170mm.
7. a kind of multichannel microphone phase calibration system using described in claim 6 is come the multichannel microphone phase realized
Calibration method, it is characterised in that：It comprises the following steps：
A. the power amplifier（1）For the loudspeaker（41）Power amplification is provided, then the loudspeaker（41）Described in
Sonic tube（42）Inside output sound pressure signal；
B. each microphone（442）Receive the sound pressure signal in step A and corresponding sound pressure signal is sent to institute
State data collecting instrument（2）In, wherein by the first modularization microphone mounting seat（44）On microphone（442）The sound of outflow
It is with reference to installation site sound pressure signal p to press signalr0(t), by remaining remaining modularization microphone mounting seat（44）On it is transaudient
Device（442）The sound pressure signal of outflow is installation site sound pressure signal pri(t)(i=1,2,3...)；
C. the data analysis terminal（3）To the data collecting instrument（2）The reference installation site sound pressure signal p collectedr0
And installation site sound pressure signal p (t)ri(t) (i=1,2,3...) progress fast Fourier changes to obtain Pr0And P (f)i(f)(i=
1,2,3…)；
D. P is takenr0And P (f)i(f) phase of (i=1,2,3 ...), so as to obtain pahse_0 (f) and phase_i (f) (i=1,2,
3…)；
E. the data analysis terminal（3）Calculate microphone phase phase_if (f) to be calibrated=phase_0 (f)-phase_r0
(f)+phase_i(f)+phase_0i(f)；
F. terminate to calibrate.
8. multichannel microphone phase calibration method according to claim 7, it is characterised in that：The step C, step D
And step E foundation formula is：
Standard microphone sensitivity (1)
Microphone i sensitivity to be calibrated (2)
It can be obtained by formula (1) and (2)：
(3)
(4)
(5)
(6)
By formula (3), (4), (5) and (6), can obtain
(7)
By formula (3) and (7), can obtain
In formula, Zr is the installation site of standard microphone, and Zi is the installation site of calibration microphone, and r is reflectance factor, Ui and
Ur is the voltage signal values of acquisition system measurement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711142402.5A CN107690121A (en) | 2017-11-17 | 2017-11-17 | Multichannel microphone phase calibration system and its calibration method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711142402.5A CN107690121A (en) | 2017-11-17 | 2017-11-17 | Multichannel microphone phase calibration system and its calibration method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107690121A true CN107690121A (en) | 2018-02-13 |
Family
ID=61154913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711142402.5A Pending CN107690121A (en) | 2017-11-17 | 2017-11-17 | Multichannel microphone phase calibration system and its calibration method |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110049424A (en) * | 2019-05-16 | 2019-07-23 | 苏州静声泰科技有限公司 | A kind of wireless calibration method of microphone array based on detection GIL knocking noise |
| CN110473514A (en) * | 2019-08-02 | 2019-11-19 | 红河学院 | A kind of device and method obtaining Standing Waves of Finite Amplitude |
| CN113079450A (en) * | 2021-04-06 | 2021-07-06 | 北京航空航天大学 | Probe type microphone calibration device and method |
| CN113841420A (en) * | 2019-05-30 | 2021-12-24 | 哈曼国际工业有限公司 | Method and system for indoor calibration in a loudspeaker system |
| CN114866945A (en) * | 2022-07-08 | 2022-08-05 | 中国空气动力研究与发展中心低速空气动力研究所 | Rapid calibration method and device for microphone array |
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2017
- 2017-11-17 CN CN201711142402.5A patent/CN107690121A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110049424A (en) * | 2019-05-16 | 2019-07-23 | 苏州静声泰科技有限公司 | A kind of wireless calibration method of microphone array based on detection GIL knocking noise |
| CN113841420A (en) * | 2019-05-30 | 2021-12-24 | 哈曼国际工业有限公司 | Method and system for indoor calibration in a loudspeaker system |
| CN113841420B (en) * | 2019-05-30 | 2024-01-16 | 哈曼国际工业有限公司 | Method and system for indoor calibration in speaker system |
| US11924625B2 (en) | 2019-05-30 | 2024-03-05 | Harman International Industries, Incorporated | Method and system for room calibration in a speaker system |
| CN110473514A (en) * | 2019-08-02 | 2019-11-19 | 红河学院 | A kind of device and method obtaining Standing Waves of Finite Amplitude |
| CN113079450A (en) * | 2021-04-06 | 2021-07-06 | 北京航空航天大学 | Probe type microphone calibration device and method |
| CN114866945A (en) * | 2022-07-08 | 2022-08-05 | 中国空气动力研究与发展中心低速空气动力研究所 | Rapid calibration method and device for microphone array |
| CN114866945B (en) * | 2022-07-08 | 2022-09-23 | 中国空气动力研究与发展中心低速空气动力研究所 | Rapid calibration method and device for microphone array |
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