An acoustic emitter based on electrical–mechanical transduction is designed to have a projected emission pattern. However, due to constructive features, design flaws, and different material qualities, the final device does not match project specifications which may cause, among other things, the reduction of performance, loss of emission power, and undesirable noise. In this work, an apparatus for acoustic characterization comprising a turntable and an arc is developed to estimate the emission power of acoustic emitters. The time-stretched pulse method is used as a test signal to obtain the emission power for each emitter's azimuth and elevation angles. Processing the acquired signals gives an estimated radiation pattern in the three-dimensional space, which visually allows the analysis of the emission characteristics of the acoustic source.

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