Truncation-error reduction in acoustic spherical near-field scanning

We have considered truncation-error reduction for acoustic spherical NF scanning. Specifically, we have discussed the expansion of truncated NF scan data in terms of the Slepian sequence that is constructed to be orthogonal over a given truncated spherical surface and have derived a NF-to-FF transformation for the resulting expansion coefficients. Numerical experiments have shown that compared with the classical algorithm this new algorithm, albeit computationally more demanding, significantly reduces the FF solution error that results when NF data is truncated.