Acoustic Beam Forming Using Ultrasonic Transducers

Abstract:

This paper evaluates the performance of acoustic beam forming using ultrasonic transducers. A directional audible sound can be generated by amplitude-modulating the ultrasound carrier with an audio signal, then transmitting it from an array of ultrasonic transducers. A novel method has been proposed in this paper to control the beam width of the main lobe and the level of the side lobe for the beam pattern by using an optimization technique. Furthermore, the weighting distribution of uniform linear array composed of eight transducers and the effect of different weightings on the spreading angle of the sound beam have been investigated through simulations in this study. The results show that the optimization method proposed in the paper can effectively control the beam width of the main lobe and the level of the side lobe for the audible sound.

• Periodical: Advanced Engineering Forum (Volume 4)
• Pages: 238-242
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.4.238
• Online since: June 2012
• Authors: Wen Kung Tseng
• Keywords: Directional Audible Sound, Optimization Technique, Ultrasonic Transducers, Ultrasound Carrier, Uniform Linear Array

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