Three-dimensional sound field reproduction based on spatial fusion of carrier and sideband waves with parametric array loudspeaker

Abstract

It is very important to provide a personal audible space (audio-spot) to listeners. Parametric array loudspeaker (PAL) has been proposed in order to provide an audio-spot because it has super directivity. It however has difficulty in reproducing the audible sound only to the particular space because the acoustic beam with the PAL is reflected and intercepted. Therefore, we have proposed the three-dimensional sound field reproduction based on spatial fusion of carrier and sideband waves with the PAL. In addition, we have proposed the method of near-sound-field reproduction based on spatial fusion of the carrier and sideband waves. In this presentation, we explain principle of the proposed method, and its applications. In the proposed method, we utilize principle which the intense ultrasound self-demodulates to the audible sound by nonlinear interaction in the air. More specifically, the intense ultrasound consists of the carrier and sideband waves, and the audible sound is demodulated as the different tone between carrier and sideband waves. The proposed method forms the audio-spot by fusing the carrier and sideband waves in the particular space. Finally, we evaluate the effectiveness of the proposed method through the evaluation experiments.