Design of transform filter for reproducing arbitrarily shifted sound field using phaseshift of spatio-temporal frequency

For real-time sound field transmission systems from a far-end to a near-end, the driving signals of a loudspeaker array at the near-end need to be calculated by using only received signals obtained by a microphone array at the far-end. Additionally, having the capability to control the location of the sound field to be reproduced in order to adjust it to the visual images is advantageous. The goal of this study was to develop a method to transform received signals of a microphone array into driv-ing signals of a loudspeaker array in order to reproduce arbi-trary shifted sound fields. We analytically derive a transform filter in the spatio-temporal frequency domain. The location of the sound field to be reproduced is controllable only by phase-shift of the transform filter. The proposed method was found to be computationally efficient compared to the conven-tional method based on a least squares algorithm, and numer-ical simulation results indicated that reproduction accuracies were almost the same in both methods. Index Terms — Sound field reproduction, wave field syn-thesis, spatial Fourier transform, acoustical holography 1