Sound Source Directivity Estimation in Spherical Fourier Domain from Sparse Measurements - Hacıhabiboğlu, Hüseyin; Olgun, Orhun (2025)
Real sound sources have unique directional properties unlike simple idealised sources such as monopoles. Measur- ing the directivity patterns of sound sources typically involves measuring sound power using pressure microphones on a spherical grid surrounding the source. This approach is not very practical and is costly due to hardware requirements. This paper proposes a reduced-complexity source directivity measurement approach. The spherical harmonic decomposition of the sound field at a small number of measurement points around the source is first obtained. Both pressure and its higher-order spatial derivatives are then calculated to estimate source directivity that best matches a fixed-order model. The proposed approach is validated to assess its utility using eight second-order measurements around a loudspeaker. The estimated directivity functions closely matched the manufacturer data, particularly at low and mid-frequency bands.
Keywords: cc-by-nc-nd-4.0; akustik; küresel harmonik