Spherical microphone arrays have been paid increasing attention for their ability to locate\na sound source with arbitrary incident angle in three-dimensional space. Low-frequency sound\nsources are usually located by using spherical near-field acoustic holography. The reconstruction\nsurface and holography surface are conformal surfaces in the conventional sound field transformation\nbased on generalized Fourier transform. When the sound source is on the cylindrical surface, it is\ndifficult to locate by using spherical surface conformal transform. The non-conformal sound field\ntransformation by making a transfer matrix based on spherical harmonic wave decomposition is\nproposed in this paper, which can achieve the transformation of a spherical surface into a cylindrical\nsurface by using spherical array data. The theoretical expressions of the proposed method are\ndeduced, and the performance of the method is simulated. Moreover, the experiment of sound source\nlocalization by using a spherical array with randomly and uniformly distributed elements is carried\nout. Results show that the non-conformal surface sound field transformation from a spherical surface\nto a cylindrical surface is realized by using the proposed method. The localization deviation is around\n0.01 m, and the resolution is around 0.3 m. The application of the spherical array is extended, and the\nlocalization ability of the spherical array is improved.
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