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Quiet Zone Design in Diffuse Fields Using Ultrasonic Transducers

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http://www.scirp.org/journal/PaperInformation.aspx?PaperID=53702#.VNBntyzQrzE

Author(s)   
Wen-Kung Tseng

Affiliation(s)
Graduate Institute of Vehicle Engineering, National Changhua University of Education, Changhua City, Taiwan.

ABSTRACT
This paper presents quiet zone design using ultrasonic transducers for local active control in pure tone diffuse fields. Most of researches in local active noise control used conventional loudspeakers for the secondary sources to produce quiet zones. Recently ultrasonic transducers have been used for the secondary sources to control the plane wave in active noise control. However there is no research related to active noise control in diffuse fields using ultrasonic transducers. Therefore this study uses ultrasonic transducers for the secondary sources to control the diffuse fields. The quiet zone produced using ultrasonic transducers in single tone diffuse fields has been analyzed through simulations in this work. The results showed that quiet zones created using ultrasonic transducers were larger than those created using conventional loudspeakers. This is due to the fact that the audible sound pressure produced by the ultrasonic transducers decays slowly with the distance. Therefore the secondary field created by an ultrasonic transducer could fit the primary field better and the larger zone of quiet could be obtained using the ultrasonic transducer. Also the audible sound produced by the ultrasonic transducers is directional; therefore the sound pressure amplification outside the quiet zones was lower.

KEYWORDS
Quiet Zone Design, Ultrasonic Transducers, Local Active Control, Diffuse Fields, Plane Wave

Cite this paper
Tseng, W. (2015) Quiet Zone Design in Diffuse Fields Using Ultrasonic Transducers. Journal of Applied Mathematics and Physics, 3, 247-253. doi: 10.4236/jamp.2015.32036.

References
[1]Tseng, W.K., Rafaely, B. and Elliott, S.J. (2000) Local Active Sound Control Using 2-Norm and ∞-Norm Pressure Minimization. Journal of Sound and Vibration, 234, 427-439. http://dx.doi.org/10.1006/jsvi.1999.2889
 
[2]Elliott, S.J. and Garcia-Bonito, J. (1995) Active Cancellation of Pressure and Pressure Gradient in a Diffuse Sound Field. Journal of Sound and Vibration, 186, 696-704. http://dx.doi.org/10.1006/jsvi.1995.0482
 
[3]Tseng, W.-K., Rafaely, B. and Elliott, S.J. (2012) A Novel Method of Designing Stable Feedback Controllers for Local Control of Sound. Journal of Vibration and Control, 18, 608-615. http://dx.doi.org/10.1177/1077546311405367
 
[4]Puttmer, A. (2006) New Applications for Ultrasonic Sensors in Process Industries. Journal of Ultrasonic, 44, 1379- 1383. http://dx.doi.org/10.1016/j.ultras.2006.05.047
 
[5]Tanaka, N. and Tanaka, M. (2010) Active Noise Control Using a Steerable Parametric Array Loudspeaker. Journal of Acoustical Society of America, 127, 3526-3537. http://dx.doi.org/10.1121/1.3409483
 
[6]Ju, H.S. and Kim, Y.H. (2010) Near-Field Characteristics of the Parametric Loudspeaker Using Ultrasonic Transducers. Journal of Applied Acoustics, 71, 793-800. http://dx.doi.org/10.1016/j.apacoust.2010.04.004
 
[7]Brooks, L.A. (2005) Investigation into the Feasibility of Using a Parametric Array Control Source in an Active Noise Control System. Proceedings of the ACOUSTICS 2005, 39-45.
 
[8]Westervelt, P.J. (1963) Parametric Acoustic Array. J. Acoust. Soc. Am., 35, 535-537. http://dx.doi.org/10.1121/1.1918525
 
[9]Tan, K.S., Gan, W.S., Yang, J. and Er, M.H. (2003) Constant Beamwidth Beamformer for Difference Frequency in Parametric Array. Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing ICASSP, Singapore, 361-364.                                                                                eww150203lx
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