Optical interferometry makes it possible to measure acoustic fields, by exploiting the acousto-optic interaction, without using microphones or other electroacoustic transducers. Scanning interferometers can sample a sound field with high spatial resolution in an automated way. Therefore, optical interferometry is particularly suitable for measuring sound fields over space at mid and high frequencies, where sampling requirements make the use of microphones demanding and costly. However, optical methods are sensitive to vibrations of the equipment that biases the measurements, especially at low frequencies. In this study we propose a joint sensing approach that combines data acquired with conventional microphones as well as with an optical interferometer. The robustness and qualitative accuracy at low frequencies is improved due to the microphone data, whereas the sound field at higher frequencies is successfully captured over space with the scanning interferometer. In an experimental study, a three dimensional acoustic field is sampled combining the two sensing methods. The results show that the frequency range in which the reconstruction is correct is extended using the joint microphone-interferometer measurements.
|Title of host publication||Proceedings of 2020 International Congress on Noise Control Engineering, INTER-NOISE 2020|
|Editors||Jin Yong Jeon|
|Publisher||Korean Society of Noise and Vibration Engineering|
|Publication date||23 Aug 2020|
|Publication status||Published - 23 Aug 2020|
|Event||49th International Congress and Exposition on Noise Control Engineering - Virtual event, Seoul, Korea, Republic of|
Duration: 23 Aug 2020 → 26 Aug 2020
|Conference||49th International Congress and Exposition on Noise Control Engineering|
|Country/Territory||Korea, Republic of|
|Period||23/08/2020 → 26/08/2020|
Bibliographical noteFunding Information:
The authors would like to thank Salvador Barrera-Figueroa from DFM for letting us the LDV. This study was supported by the VILLUM foundation (grant number 19179).
© Proceedings of 2020 International Congress on Noise Control Engineering, INTER-NOISE 2020. All rights reserved.