Continuous measurement of spatial room impulse responses using a non-uniformly moving microphone

Abstract

The room impulse responses at multiple receiver positions can be measured efficiently with a continuously moving microphone. The acoustic system is periodically excited by a self-orthogonal signal, called perfect sequence, and the microphone captures the sound field on a pre-defined path. As shown in recent studies by the authors, the captured signal constitutes a spatio-temporal sampling of the sound field, and the impulse responses can be obtained by a spatial interpolation. So far, a uniformly moving microphone was mainly considered for the measurement of spatial room impulse responses. In this paper, the method is applied to non-uniformly moving microphones thereby addressing more general cases. The proposed method is evaluated by numerical simulations where the spatial room impulse responses on a circle are measured using a microphone with a fluctuating angular speed. The accuracy of the impulse responses are compared for varying interpolation orders.