Audio Application of the Parametric Array – Implementation through a Numerical Model

摘要

Implementing the parametric array for audio applications is examined through numerical modeling andanalytical approximation. The analytical solution of the nonlinear wave equation is used to provideguidelines on the design parameters of the parametric array. The solution relates the source size, inputpressure level, and the carrier frequency to the audible signal response including the output level, beamwidth, and length of the interaction region. A time domain finite difference code that accurately solvesthe KZK nonlinear parabolic wave equation is used to predict the response of the parametric array. Theaccuracy of the numerical model is established by a simple parametric array experiment. In consideringthe implementation issues for audio applications of the parametric array, the emphasis is given to thepoor frequency response and the harmonic distortion. Signal processing techniques to improve thefrequency response and the harmonic distortion are suggested and implemented through the numericalsimulation.