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Showing 1 to 5 of 5 for “"acoustic arrays"”.
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Analog Single Sideband-Pulse Width Modulation Processor for Parametric Acoustic Arrays
<p>Parametric acoustic arrays are ultrasonic-based loudspeakers that produce highly directive audio. The audio must first be preprocessed and modulated into an ultrasonic carrier before being emitted into the air, where it will self-demodulate in the far field. The resulting audio wave is …
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Optimization of transmit/receive array topology in 3D acoustic imaging
Acoustic imaging transmit and receive arrays pairs are simulated in the bistatic transmission case using Field II, an industry standard ultrasound toolbox. Analysis of imaging fundamentals, as well as simple transmit and receive array beam patterns reveals desirable beam pattern properties that can …
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Structure of an Ensemble of Insectivorous Bats
… flight behaviour, habitat use, and diet. Using acoustic arrays I compared activity patterns at different sites to determine temporal and spatial partitioning and generated flight paths to determine flight speeds. From captured bats I measured wing morphology to examine morphological differences …
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Sound Propagation via Narrow Beam Audio Projection
The parametric acoustic array is a nonlinear phenomenon of physics theoretically described over fifty years ago. It consists in the generation of secondary sound waves by the propagation of two collimated primary ultrasonic waves at a close frequency. The sound wave generated corresponds to the …
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Reduction of Near-Field Grating Lobes in Sparse Acoustic Phased Arrays
<p>Acoustic phased arrays with inter-element spacings of greater than one half-wavelength will produce grating lobes that decrease the usefulness of the array. With many array configurations, the near-field and far-field character of these lobes is significantly different -- an optimization of the …