Development of a steerable stereophonic parametric loudspeaker

The parametric loudspeaker is a type of directional loudspeakers making use of the nonlinear acoustic effects. The past studies to reproduce the three-dimensional audio contents with a pair of the parametric loudspeakers have demonstrated satisfactory performance. In this paper, the steerable parametric loudspeakers are proposed to relocate the sweet spot to follow the head movement of the listener. Although the spatial aliasing effects are observed in the steerable parametric loudspeaker, they can be converted to generate multiple sound beams simultaneously. A new case of the grating lobe elimination, namely the over elimination, is studied to extend the controllable level difference between the two sound beams. The simulation results to compare the equal and Chebyshev weights are also presented in this paper.