Abstract
In this paper, we discuss an approach of S/N ratio improvement for an optical wave microphone. With the optical wave microphone, ultra-weak diffraction light; which is resulting from phase modulation from a sound wave, is converted to an electrical signal using a light detector. In this way the optical wave microphone can detect the sound without making any contact with others. Signal intensity could be increased or S/N ratio could be improved with (1) optical method, (2) method using electrical circuit, or (3) method using information processing. In this study, we adopted wavelet network as one of the methods using information processing. As a result we succeeded noise reduction at low frequency using only proposed algorithm, not by using combination of various filters.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Sonoda, Y., Akazaki, M.: Measurement of Low-Frequency Ultrasonic Waves by Fraunhofer Diffraction. Jpn. J. Appl. Phys. 33(pt. 1, 5B), 3110–3114 (1994)
Sonoda, Y.: Direct detection of acoustic waves by laser light diffraction and proposals of the optophone. In: Proc.16th Int. Cong. on Acoust. and 135th Meet. of Acoust. Soc. America, vol. 1, pp. 427–428 (1996)
Goodman, J.W.: Introduction to Fourier Optics, 3rd edn. Roberts & Company Publishers (2005)
Evans, D.E., von Hellermann, M., Holzhauer, E.: Fourier optics approach to far forward scattering and related refractive index phenomena in laboratory plasmas. Plasma Phys. 24, 819–834 (1982)
Sonoda, Y., Suetsugu, Y., Muraoka, K., Akazaki, M.: Applications of the Fraunhofer-diffraction method for plasma-wave measurements. Plasma Phys. 25, 1113–1132 (1983)
Tanaka, K., Nogami, G., Sonoda, Y.: Measurement of Audible Acoustic Wave by Laser Light. The Transactions of the Institute of Electrical Engineers of Japan 122-E(7), 362–368 (2002)
Morlet, J., Arens, G., Fourgeau, E., Giard, D.: Wave Propagation and Sampling Theory - Part 1: Complex Signal and Scattering in Multilayered Media. Geophysics 47(2), 203–221 (1982)
Morlet, J., Arens, G., Fourgeau, E., Giard, D.: Wave Propagation and Sampling Theory - Part 2: Sampling Theory and Complex Waves. Geophysics 47(2), 222–236 (1982)
Yamakawa, T., Uchino, E., Samatsu, T.: Wavelet Neural Networks Employing Over Complete Number of Compactly Supported Non-Orthogonal Wavelet and Their Applications. In: Proc. IEEE Int. Conf. on Neural Networks, pp. 1391–1396 (1994)
Yamakawa, T., Uchino, E., Samatsu, T.: The Wavelet Network Using Convex Wavelets and Its Application to Modeling of Dynamical Systems. The Transactions on the IEICE J79-A(12), 2046–2053 (1996) (in Japanese)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer International Publishing Switzerland
About this paper
Cite this paper
Samatsu, T., Sonoda, Y. (2014). SNR Improvement of an Optical Wave Microphone Using a Wavelet Network. In: Rhee, SY., Park, J., Inoue, A. (eds) Soft Computing in Machine Learning. Advances in Intelligent Systems and Computing, vol 273. Springer, Cham. https://doi.org/10.1007/978-3-319-05533-6_9
Download citation
DOI: https://doi.org/10.1007/978-3-319-05533-6_9
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-05532-9
Online ISBN: 978-3-319-05533-6
eBook Packages: EngineeringEngineering (R0)