Optimal model-based beamforming and independent steering for spherical loudspeaker arrays (2310.04202v1)
Abstract: Spherical loudspeaker arrays have been recently studied for directional sound radiation, where the compact arrangement of the loudspeaker units around a sphere facilitated the control of sound radiation in three-dimensional space. Directivity of sound radiation, or beamforming, was achieved by driving each loudspeaker unit independently, where the design of beamforming weights was typically achieved by numerical optimization with reference to a given desired beam pattern. This is in contrast to the methods already developed for microphone arrays in general and spherical microphone arrays in particular, where beamformer weights are designed to satisfy a wider range of objectives, related to directivity, robustness, and side-lobe level, for example. This paper presents the development of a physical-model-based, optimal beamforming framework for spherical loudspeaker arrays, similar to the framework already developed for spherical microphone arrays, facilitating efficient beamforming in the spherical harmonics domain, with independent steering. In particular, it is shown that from a beamforming perspective, the spherical loudspeaker array is similar to the spherical microphone array with microphones arranged around a rigid sphere. Experimental investigation validates the theoretical framework of beamformer design.
- O. Warusfel and N. Misdariis, “Directivity synthesis with a 3d array of loudspeakers: application for stage performance,” in Proceedings of the COSTG-6 Conference on Digital Audio Effects (DAFX-Ol), Limerick, Ireland, 2001.
- R. Avizienis, A. Freed, P. Kassakian, and D. Wessel, “A compact 120 independent element spherical loudspeaker array with programmable radiation patterns,” in Proceedings of the 120th Audio Engineering Society Convention, Paris, no. 6783, 2006.
- B. Rafaely, “Spherical loudspeaker array for local active control of sound,” J. Acoust. Soc. Am., vol. 125, no. 5, pp. 3006–3017, May 2009.
- F. Zotter and R. Höldrich, “Modeling of radiation synthesis with spherical loudspeaker arrays,” in Proceedings of the 19th International Congress on Acoustics, Madrid, no. COM-01-006, September 2007.
- A. M. Pasqual, J. R. de Franca Arruda, and P. Herzog, “Application of Acoustic Radiation Modes in the Directivity Control by a Spherical Loudspeaker Array,” Acta Acustica united with Acustica, vol. 96, no. 1, pp. 32–42, 2010.
- M. Pollow and G. K. Behler, “Variable directivity for platonic sound sources based on spherical harmonics optimization,” Acta Acoustics united with Acoustica, vol. 95, pp. 1082–1092, 2009.
- J. Meyer and G. W. Elko, “A highly scalable spherical microphone array based on an orthonormal decomposition of the soundfield,” Proceedings ICASSP 2002, vol. II, pp. 1781–1784, 2002.
- B. Rafaely, “Analysis and design of spherical microphone arrays,” IEEE Trans. Speech Audio Proc., vol. 13, no. 1, pp. 135–143, January 2005.
- B. Rafaely, Y. Peled, M. Agmon, D. Khaykin, and E. Fisher, “Spherical microphone array beamforming,” in Speech Processing in Modern Communications: challenges and perspectives, I. Cohen, J. Benesty, and S. Gannot, Eds. Berlin: Springer-Verlag, 2010, ch. 11, pp. 281–305.
- F. Zotter and R. Höldrich, “Modeling a spherical loudspeaker system as a multipole source,” in Proceedings of the 33rd German Annual Conference on Acoustics, Stuttgart, March 2007.
- B. Rafaely, “Phase-mode versus delay-and-sum spherical microphone array processing,” IEEE Sig. Proc. Let., vol. 12, no. 10, pp. 713–716, October 2005.