Robust spherical harmonic domain interpolation of spatially sampled array manifolds

Accurate interpolation of the array manifold is an important first step for the acoustic simulation of rapidly moving microphone arrays. Spherical harmonic domain interpolation has been proposed and well studied in the context of head-related transfer functions but has focussed on perceptual, rather than numerical, accuracy. In this paper we analyze the effect of measurement noise on spatial aliasing. Based on this analysis we propose a method for selecting the truncation orders for the forward and reverse spherical Fourier transforms given only the noisy samples in such a way that the interpolation error is minimized. The proposed method achieves up to 1.7 dB improvement over the baseline approach.