Abstract
Measurement microphones are typically calibrated in a free field at frequencies up to 50 kHz. This is a sufficiently
high frequency for the most of sound measurement applications related with noise assessment.
However, other applications such as assessment of the noise emitted by ultrasound cleaning machines, and
fail detection in aeronautic structures require that the sensitivity of the microphone is known at frequencies
up to 150 kHz. Such a high frequency can only be reached using small measurement microphones with very
low sensitivity. Thus, in order to extend the frequency range of free-field calibration the measurement system,
and measurement methods must undergo a series of changes and adaptations including the type of measurement
signal, methods for eliminating unwanted reflections from walls, cross-talk, etc. Furthermore, the
properties of the measurement microphones used in high frequency calibration are relatively less known, and
must be determined either from experimental methods or numerically. This paper presents the results of an
initial investigation of the calibration of measurement microphones at high frequencies. A strategy for the
changes and adaptations to the existing measurement methodologies, and the determination of the microphone
parameters is outlined.
Original language | English |
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Title of host publication | INTER- NOISE 2011 Proceedings |
Publication date | 2011 |
Publication status | Published - 2011 |
Event | INTER-NOISE 2011 : 40th International Congress and Exposition on Noise Control Engineering - Osaka, Japan Duration: 4 Sept 2011 → 7 Sept 2011 Conference number: 40 |
Conference
Conference | INTER-NOISE 2011 : 40th International Congress and Exposition on Noise Control Engineering |
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Number | 40 |
Country/Territory | Japan |
City | Osaka |
Period | 04/09/2011 → 07/09/2011 |
Keywords
- Free-field reciprocity
- Microphone calibration