2021 IEEE International Conference on Acoustics, Speech and Signal Processing

6-11 June 2021 • Toronto, Ontario, Canada

Extracting Knowledge from Information

2021 IEEE International Conference on Acoustics, Speech and Signal Processing

6-11 June 2021 • Toronto, Ontario, Canada

Extracting Knowledge from Information

Technical Program

Paper Detail

Paper IDSAM-5.4
Paper Title CHARACTERIZATION OF MEMS MICROPHONE SENSITIVITY AND PHASE DISTRIBUTIONS WITH APPLICATIONS IN ARRAY PROCESSING
Authors Patrick W.A. Wijnings, Eindhoven University of Technology / Sorama, Netherlands; Sander Stuijk, Eindhoven University of Technology, Netherlands; Rick Scholte, Sorama, Netherlands; Henk Corporaal, Eindhoven University of Technology, Netherlands
SessionSAM-5: Microphone Array Signal Processing
LocationGather.Town
Session Time:Thursday, 10 June, 14:00 - 14:45
Presentation Time:Thursday, 10 June, 14:00 - 14:45
Presentation Poster
Topic Sensor Array and Multichannel Signal Processing: [SAM-CALB] Array calibration
IEEE Xplore Open Preview  Click here to view in IEEE Xplore
Virtual Presentation  Click here to watch in the Virtual Conference
Abstract An array with MEMS microphones can distinguish individual noise sources in an environment through spatial filtering. Its effectiveness depends on the variations in microphone sensitivity and phase. Quantification of these variations is valuable, because it enables assessment and optimization of array performance. This is particularly important if the measurements are to be used for enforcement of noise regulations. Nominal microphone sensitivity and phase are manufacturer-specified, but the distribution (histogram) around these values is not. Hence, this work demonstrates a free-field comparison method for measuring these variations in a batch of arrays. We also provide the histograms at 1 kHz for a sample population of 8384 Knowles SPH0641LM4H-1 MEMS microphones (131 arrays of 64 microphones). The histograms follow t-distributions, resulting in 95% confidence intervals of ±0.39 dB for sensitivity and ±0.82° for phase. Finally, we illustrate that delay-and-sum beamforming with these microphones results in a Gumbel-distributed gain with -0.13/+0.10 dB 95% confidence interval.