A study on calibration frequency limit of acoustic chamber type microphone calibrator and improvement method using mode shape

Chayeong Kim; Kumjae Shin; Wonkyu Moon

doi:10.7776/ASK.2022.41.1.001

All Issue

2022 Vol.41, Issue 1 Next Page

Research Article

A study on calibration frequency limit of acoustic chamber type microphone calibrator and improvement method using mode shape 음향 챔버형 마이크로폰 검교정기의 검교정 주파수 한계와 모드 특성을 이용한 개선 방법에 관한 연구

January 2022. pp. 1-8

PDF XML

Abstract

This paper identifies the cause of the high frequency calibration limit of the acoustic chamber type calibrator for microphone calibration and presents a method to improve it. By using a commercial finite element analysis software, we analyzed the calibration frequency limit of the acoustic chamber type calibrator through eigen-frequency and frequency domain analysis. Based on this, we designed and fabricated an acoustic chamber type calibrator that can precisely calibrate within 1 dB from about 2 Hz to 6.4 kHz and verified its performance through experiments. The acoustic chamber type calibrator fabricated through this study has the advantage of being able to calibrate multiple microphones simultaneously in a wide frequency range, so it can be usefully used for simple calibration for multiple microphones.

Keywords

Microphone

Microphone calibrator

Sensitivity measurement

Acoustic chamber

Mode shape

본 논문은 마이크로폰 검교정을 위한 음향 챔버형 검교정기의 고주파 검교정 한계가 나타나는 원인을 밝히고 이를 향상시키는 방법을 제시한다. 상용 유한요소 해석 프로그램을 활용하여 고유 주파수 해석과 주파수 영역 해석을 통해 음향 챔버형 검교정기의 검교정 주파수 한계를 분석하였고, 이를 바탕으로 약 2 Hz 부터 6.4 kHz 까지 1 dB 수준 이내로 정교하게 검교정할 수 있는 음향 챔버형 검교정기를 설계 및 제작하고 실험을 통해 그 성능을 검증하였다. 본 연구를 통해 제안된 음향 챔버형 검교정기는 넓은 주파수 범위에서 다수의 마이크로폰을 동시에 검교정 할 수 있는 이점을 가지고 있어 다수의 마이크로폰을 위한 간편한 검교정에 유용하게 사용될 수 있다.

키워드

마이크로폰

마이크로폰 검교정기

감도 측정

음향 챔버

모드 형상

References

G. S. K. Wong and T. F. W. Embleton, AIP Handbook of Condenser Microphones : Theory, Calibration, and Measurements (AIP Press, New York, 1995), pp. 70-254.

E. Frederiksen, "Acoustic metrology - an overview of calibration methods and their uncertainties," IJMQE. 4, 97-107 (2013). 10.1051/ijmqe/2013045

E. Frederiksen, "Pressure reciprocity calibration -instrumentation, results and uncertainty," Brüel & Kjær, B&K Tech. Review No. 1, 1998.

T. D. Rossing, Handbook of Acoustics (Springer, New York, 2007), pp. 1021-1052. 10.1007/978-0-387-30425-0

R. Barham, S. Barrera-Figueroa, and J. E. M. Avison, "Secondary pressure calibration of measurement microphones," Metrologia, 51, 129-138 (2014). 10.1088/0026-1394/51/3/129

Brüel & Kjær (Model : B&K 9757), B&K Product Data, https://www.bksv.com/en/calibration/calibration-systems/microphone-calibration-systems/low-frequency-calibration-system, (Last viewed January 4, 2022).

GRAS (Model : GRAS 42AE), GRAS Product Data, https://www.grasacoustics.com/products/calibration-equipment/low-frequency-calibrator/product/260-42ae, (Last viewed January 4, 2022).

J. R. Oldham, J. D. Sagers, J. D. Blotter, S. D. Sommerfeldt, T. W. Leishman, and K. L. Gee, "Development of a multi-microphone calibrator," Applied Acoustics, 70, 790-798 (2009). 10.1016/j.apacoust.2008.09.013

Brüel & Kjær (Model : B&K 4192), B&K Product Data, https://www.bksv.com/-/media/literature/Product-Data/bp2213.ashx, (Last viewed January 4, 2022).

Brüel & Kjær (Model : B&K 4193), B&K Product Data, https://www.bksv.com/-/media/literature/Product-Data/bp2214.ashx, (Last viewed January 4, 2022).

Information

Publisher :The Acoustical Society of Korea
Publisher(Ko) :한국음향학회
Journal Title :The Journal of the Acoustical Society of Korea
Journal Title(Ko) :한국음향학회지
Volume : 41
No :1
Pages :1-8
Received Date : 2021-11-09
Revised Date : 2022-01-04
Accepted Date : 2022-01-05
DOI :https://doi.org/10.7776/ASK.2022.41.1.001

The Journal of the Acoustical Society of KoreaISSN:1225-4428(Print) 2287-3775(Online)한국음향학회

All Issue