Application of MEMS microphone array for acoustic holography
Regular paper
Brno University of Technology
Tuesday 2 june, 2015, 11:00 - 11:20
0.8 Rome (118)
Abstract:
The paper shows the overall potential and applicability of microphone arrays
equipped with MEMS miniature capacitive microphones for use with near-field
acoustic holography algorithms to visualize and localize sound sources.
Comprehensive test of double layer rectangular matrix microphone array and
several
acoustic holography algorithms has been carried out to find weaknesses of
proposed
MEMS array technology in practical measurement conditions including complex
sources and disturbing sound field. Test setups include determination of
secondary
(disturbing) source strength, influence of distance of the primary and
secondary
sources, measurement array stand-off distance, prediction plane and virtual
source
plane position on prediction accuracy of localization and characterization of
sound and vibration sources. Attention is also focused on possibilities of
MEMS
microphone pressure amplitude phase mismatch evaluation and calibration as
well as
minimization of influence of digital signal processing of digital PDM output
of
MEMS microphones. Applicability of specific regularization parameter selection
methods for sound field prediction based on acoustic holography algorithms for
this type of array is also discussed.